BlogJava-Java,永远不敢言精通-随笔分类-Android

android 线条选择器

Ying-er — Wed, 30 Jan 2013 03:27:00 GMT

如下图所示，本文将介绍如何通过修改EditText里的值，动态的改变所画Line的宽度（只介绍大概思路）

1.定义一个layout，用于放置Line

2.在自定义View里画Line

Paint paint = new Paint();
paint.setStrokeWidth(this.width);
canvas.drawLine(this.getWidth(), 10, 0, this.getHeight() - 10,
paint);

其中，width就是EditText里传过来的宽度

3.将自定义的View放到【1】的layout里

widthLayout = (LinearLayout) view
                .findViewById(R.id.ll_feature_width_legend);
        widthLegend = new DBLayerListSymbolView(this.activity, width);
        widthLayout.addView(widthLegend);

其中， DBLayerListSymbolView是自定义的View，width是EditText传过来的宽度

4.在自定义的View里追加如下代码，以动态改变width的值，并刷新界面

/**
     * change symbol draw width
     *
     * @param width
     */
    public void changeWidth(float width) {
        this.width = width;
        invalidate();
    }

5.给EditText追加TextChangedListener，实现其中的onTextChanged方法：

@Override
            public void onTextChanged(CharSequence text, int arg1, int arg2,
                    int arg3) {
                float width = Float.parseFloat(text.toString());
                if (width >= 0 && width <= 20) {
                    mWidth = width;
                    widthLegend.changeWidth(width);
}
            }

这样，随着EditText里值的变化，旁边白色区域内就能够动态的显示对应宽度的线条

本文受启发于：http://nxsfan.co.uk/blog/2010/06/18/ondraw-drawing-a-simple-line-on-a-background/

另外，最近发现了个不错的jar包下载网站：http://jarfiles.pandaidea.com/

Ying-er 2013-01-30 11:27 发表评论

Step by Step——Google Map View2 （i am here）

Ying-er — Fri, 14 Oct 2011 02:01:00 GMT

摘要: TODO：对上一篇随笔：Step by Step——Google Map View（Hello View）进行进一步改进，使其能够获取设备当前位置，并显示对应地图 step1：定义LocationManager，获取当前location，并封装成GeoPoint loc... 阅读全文

Ying-er 2011-10-14 10:01 发表评论

Step by Step——Google Map View（Hello View）

Ying-er — Wed, 12 Oct 2011 07:47:00 GMT

摘要: 今天参照Android Api里的Hello Views来学习GMap，不想，Api里好多错误，囧 so，我在这里贴出正确的代码，供大家参考 TODO（1）：显示Map（Creating a Map Activity） step1：创建一个新的工程 step2：由于Maps library不是标准库里的东东，SO，要在AndroidManifest.xml文件中加上一个library：... 阅读全文

Ying-er 2011-10-12 15:47 发表评论

#Android java.lang.ClassNotFoundException: ...in loader dalvik.system.PathClassLoader@43b7d6d0

Ying-er — Tue, 11 Oct 2011 05:32:00 GMT

加入节点：users-library

activity>
<uses-library android:name = "com.google.android.maps"/>
application>

Ying-er 2011-10-11 13:32 发表评论

#Android com.google.android.maps.MapView in loader dalvik.system.PathClassLoader@43b7d6d0

Ying-er — Tue, 11 Oct 2011 05:26:00 GMT

没有继承 MapActivity
eg：

public class GMapTest extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}

改成：

public class GMapTest extends MapActivity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    @Override
    protected boolean isRouteDisplayed() {
        // TODO Auto-generated method stub
        return false;
    }
}

Ying-er 2011-10-11 13:26 发表评论

#Android 获取(keystore)Maps API Key

Ying-er — Tue, 11 Oct 2011 02:36:00 GMT

(Getting the MD5 Fingerprint of the SDK Debug Certificate)

申请网址：http://code.google.com/intl/en/android/add-ons/google-apis/mapkey.html

①打开cmd窗口，到.android目录下
②按照$ keytool -list -alias alias_name -keystore my-release-key.keystore格式敲入命令
③输入密码：android
④获取到指纹
附截图：

⑤到网址：http://code.google.com/intl/en/android/add-ons/google-apis/maps-api-signup.html

勾选I have read and agree with the terms and conditions (printable version)
输入刚刚获取到的指纹
点击Generate API Key
⑥获取到指纹所对应的密钥，并保存好，页面上提供了一段测试代码，不妨顺手试试。

附：Debug Key的相关参数
Keystore name：debug.keystore
Keystore password:android
Key alias:androiddebugkey
Key password:android
CN:CN=Android Debug,O=Android，C=US

Ying-er 2011-10-11 10:36 发表评论

在Android模拟器里安装apk

Ying-er — Tue, 11 Oct 2011 01:25:00 GMT

①找到tools目录
eg：
D:\Android\android-sdk_r05-windows\android-sdk-windows\platform-tools

②打开cmd窗口，路径切换到tools下

③adb install XXX.apk

Ying-er 2011-10-11 09:25 发表评论

#Android 获得当前设备上可用Location Provider列表

Ying-er — Wed, 28 Sep 2011 07:30:00 GMT

LocationManager locationManager;

locationManager = (LocationManager)UserLocationTest.this.getSystemService(Context.LOCATION_SERVICE);

List<String> providers = locationManager.getAllProviders();
            for(Iterator iterator = providers.iterator();iterator.hasNext();)
            {
                String provider = (String)iterator.next();
                System.out.println("====" + provider + "===");
            }

Ying-er 2011-09-28 15:30 发表评论

#Android 使用User Location获取当前经纬度

Ying-er — Sun, 25 Sep 2011 13:28:00 GMT

step1：声明权限

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

step2：获取LocationManager对象

LocationManager locationManager = (LocationManager)LocationTest.this.getSystemService(Context.LOCATION_SERVICE);

step3：选择LocationProvider，绑定LocationListener对象

locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, new MyLocationListener());

附：MyLocationListener

    private class MyLocationListener implements LocationListener{

        @Override
        public void onLocationChanged(Location location) {
            // TODO Auto-generated method stub
            System.out.println(location.getLatitude());
            System.out.println(location.getLongitude());
        }

        @Override
        public void onProviderDisabled(String provider) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onProviderEnabled(String provider) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {
            // TODO Auto-generated method stub

        }

    }

Ying-er 2011-09-25 21:28 发表评论

Spinner 使用方法小结

Ying-er — Sat, 09 Jul 2011 08:15:00 GMT

android里的Spinner其实就是个ComboBox =。=
一。基本使用方法：
main.xml 不多解释

xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<Spinner
     android:id = "@+id/mySpinner"
     android:layout_width = "fill_parent"
     android:layout_height ="wrap_content"
     />
LinearLayout>

在string.xml中使用“string-array”定义数据源。

xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="app_name">MySpinnerDemostring>
    <string-array name = "phones_array">
        <item>iPhoneitem>
        <item>Androiditem>
        <item>BlackBerryitem>
    string-array>
resources>

Activity类：

package com.yinger;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.AdapterView.OnItemSelectedListener;

/**
* Spinner Demo
* @author Yinger
* @time 2011-7-9 下午01:54:59
* @mail melody.crazycoding@gmail.com
*/
public class SpinnerDemo extends Activity {
    Spinner spinner = null;
    String selected = "0";

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        spinner = (Spinner)findViewById(R.id.mySpinner);
        initMySpinner();
    }

    private void initMySpinner() {
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(
                this, R.array.phones_array,
                android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(adapter);
        spinner.setPrompt("test");
        spinner.setOnItemSelectedListener(new SpinnerOnSelectedListener());
    }

    class SpinnerOnSelectedListener implements OnItemSelectedListener{
        public void onItemSelected(AdapterView adapterView, View view, int position,
                long id) {
            // TODO Auto-generated method stub
            selected = adapterView.getItemAtPosition(position).toString();
            System.out.println("selected===========>" + selected);
        }

        public void onNothingSelected(AdapterView arg0) {
            // TODO Auto-generated method stub
            System.out.println("selected===========>" + "Nothing");
        }
    }
}

二。debug发现的一个小问题：
Spinner在初始化时会自动调用一次OnItemSelectedListener事件
原因：有人说是Bug，其实这与C#的事件机制类似，懒得说了=。=
提供的解决办法：
个人是通过在事件注册之前调用

spinner.setSelection(0, true);

但要注意，使用此方法，如果用户选择的也是第一项，那么OnItemSelectedListener事件不会被触发……

三。使用技巧
1.动态添加Spinner的数据源
修改initMySpinner方法，代码如下：

private void initMySpinner() {
        String[] phones = {"iPhone","Android","BlackBerry"};
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(
                this,  android.R.layout. simple_spinner_item,
                phones);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(adapter);
        spinner.setPrompt("test");
        spinner.setSelection(0, true);
        spinner.setOnItemSelectedListener(new SpinnerOnSelectedListener());
    }

2.自定义Spinner的Layout，替换掉体统默认的android.R.layout.simple_spinner_item
super easy
my_spinner_item.xml:

xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:textSize="12dip"
    android:textColor="#FF8B1500"
    android:gravity="center" />

修改adapter：

ArrayAdapter<String> adapter = new ArrayAdapter<String>(
this, R.layout.my_spinner_item,
phones);

同理，可自定义layout，替换掉android.R.layout.simple_spinner_dropdown_item

3.同时显示图片和文本
自定义Adapter：

package com.yinger;

import android.content.Context;
import android.graphics.Color;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

/**
* 自定义Adapter
* @author Yinger
* @time 2011-7-9 下午03:39:34
* @mail melody.crazycoding@gmail.com
*/
public class MyAdapter extends BaseAdapter {

    private Context ctx;
    private int drawableIDs[];
    private int stringIDs[];

    public MyAdapter(Context ctx, int DrawableIDs[], int StringIDs[])
    {
        this.ctx = ctx;
        this.drawableIDs = DrawableIDs;
        this.stringIDs = StringIDs;
    }

    public int getCount() {
        // TODO Auto-generated method stub
        return drawableIDs.length ;
    }

    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return drawableIDs [position];
    }

    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        LinearLayout ll = new LinearLayout( ctx );
        ll.setOrientation(LinearLayout. HORIZONTAL );
        ll.setGravity(Gravity. CENTER_VERTICAL );
        ImageView iv = new ImageView( ctx );
        iv.setImageResource( drawableIDs [position]);
        iv.setLayoutParams( new ViewGroup.LayoutParams(100, 40));
        ll.addView(iv);
        TextView tv = new TextView( ctx );
        tv.setText( stringIDs [position]);
        tv.setTextSize(14);
        tv.setTextColor(Color.BLUE );
        ll.addView(tv);
        return ll;
    }
}

修改initMySpinner方法：

private void initMySpinner() {
        int[] phonePics = {R.drawable.apple,R.drawable.android,R.drawable.blackberry};
        int[] phones = {   R.string.iphone, R.string.android,  R.string.blackberry};

        MyAdapter adapter = new MyAdapter(this,phonePics,phones);
        spinner.setAdapter(adapter);
        spinner.setPrompt("test");
        spinner.setSelection(0, true);
    }

运行结果截图：

OK，但使用自定义的Adapter，我们如何来获取选中的文本信息呢？
在MyAdapter中，修改getView方法，添加黄色区域代码如下：

public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        LinearLayout ll = new LinearLayout( ctx );
        ll.setOrientation(LinearLayout. HORIZONTAL );
        ll.setGravity(Gravity. CENTER_VERTICAL );
        ImageView iv = new ImageView( ctx );
        iv.setImageResource( drawableIDs [position]);
        iv.setLayoutParams( new ViewGroup.LayoutParams(100, 40));
        ll.addView(iv);
        TextView tv = new TextView( ctx );
        tv.setText( stringIDs [position]);
        tv.setTextSize(14);
        tv.setTextColor(Color.BLUE );
        tv.setTag( "tagTextView" );
        ll.addView(tv);
        return ll;
    }

重写事件中的onItemSelected方法：

// TODO Auto-generated method stub
        public void onItemSelected(AdapterView adapterView, View view, int position,
                long id) {
            if(adapterView.getId() == R.id.mySpinner)
            {
                LinearLayout ll = (LinearLayout)view;
                TextView tv = (TextView)ll.findViewWithTag( "tagTextView" );
                String str = (String)tv.getText();
                System.out.println("selected===========>" + str);
            }
        }

最后，别忘了注册该事件。=。=

Ying-er 2011-07-09 16:15 发表评论

Android 创建复合控件

Ying-er — Sun, 12 Jun 2011 01:53:00 GMT

①自定义复合控件的布局：

clearable_edit_text.xml:

xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation = "horizontal">
  <EditText
      android:id = "@+id/editText"
      android:layout_width = "200dp"
      android:layout_height = "wrap_content"
      />
  <Button
      android:id = "@+id/clearButton"
      android:layout_width = "100dp"
      android:layout_height = "wrap_content"
      android:text = "Clear"
      />
LinearLayout>

很简单，不废话

②选择适合放置子控件的布局类，并将其扩展

package com.yinger;

import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;

public class MyClearableEditText extends LinearLayout {

    EditText editText;
    Button clearButton;

    public MyClearableEditText(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub
        init();
        hookupButton();
    }

    public MyClearableEditText(Context context) {
        super(context);
        init();
        hookupButton();
    }

    private void init() {
        String infService = Context.LAYOUT_INFLATER_SERVICE;
        LayoutInflater li;
        li = (LayoutInflater) getContext().getSystemService(infService);
        li.inflate(R.layout.clearable_edit_text, this, true);
        editText = (EditText) findViewById(R.id.editText);
        clearButton = (Button) findViewById(R.id.clearButton);
    }

//    private void init2() {
//        setOrientation(LinearLayout.VERTICAL);
//        editText = new EditText(getContext());
//        clearButton = new Button(getContext());
//        clearButton.setText("Clear");
//        int lHeight = LayoutParams.WRAP_CONTENT;
//        int lWidth = LayoutParams.FILL_PARENT;
//
//        addView(editText,new LinearLayout.LayoutParams(lWidth,lHeight));
//        addView(clearButton,new LinearLayout.LayoutParams(lWidth,lHeight));
//    }

    private void hookupButton(){
        clearButton.setOnClickListener(new Button.OnClickListener(){

            public void onClick(View v) {
                // TODO Auto-generated method stub
                editText.setText("");
            }
        });
    }
}

③引用

xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/hello"
    />
<com.yinger.MyClearableEditText
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
/>
LinearLayout>

Ying-er 2011-06-12 09:53 发表评论

自定义android控件——TextView 并添加到ListView中

Ying-er — Sat, 11 Jun 2011 13:26:00 GMT

①在values文件夹下定义TextView的颜色和边距规则：

颜色规则：notepadcolors.xml

xml version="1.0" encoding="utf-8"?>
<resources>

  <color name="notepad_paper">#AAFFFF99color>

  <color name="notepad_lines">#FF0000FFcolor>

  <color name="notepad_margin">#90FF0000color>

  <color name="notepad_text">#AA0000FFcolor>
resources>

边距规则：notepaddimens.xml

xml version="1.0" encoding="utf-8"?>
<resources>
<dimen name="notepad_margin">30dpdimen>
resources>

②创建一个扩展原TextView的新类，并重写onDraw方法来修改视图的外观

package com.yinger;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.widget.TextView;

public class TodoListItemView extends TextView {

    private Paint marginPaint;
    private Paint linePaint;
    private int paperColor;
    private float margin;

    public TodoListItemView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        // TODO Auto-generated constructor stub
        init();
    }

    public TodoListItemView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public TodoListItemView(Context context) {
        super(context);
        init();
    }

    private void init() {
        Resources myResources = getResources();
        // Create the paint brushes we will use in the onDraw method.
        marginPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        marginPaint.setColor(myResources.getColor(R.color.notepad_margin));

        linePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        linePaint.setColor(myResources.getColor(R.color.notepad_lines));

        // Get the paper background color and the margin width.
        paperColor = myResources.getColor(R.color.notepad_paper);
        margin = myResources.getDimension(R.dimen.notepad_margin);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        // TODO Auto-generated method stub
        // Color as paper
        canvas.drawColor(paperColor);

        // Draw ruled lines
        canvas.drawLine(0, 0, 30.0f, 0, linePaint);
        canvas.drawLine(0, getMeasuredHeight(),
                           getMeasuredWidth(), getMeasuredHeight(),
                           linePaint);

        // Draw margin
        canvas.drawLine(margin, 0, margin, getMeasuredHeight(), marginPaint);

        // Move the text across from the margin
        canvas.save();
        canvas.translate(margin, 0);

        // Use the TextView to render the text.
        super.onDraw(canvas);
        canvas.restore();
    }
}

注：要重写所有的构造方法，这样比较保险。

-----------------------------------------------------------我是分隔线-------------------------------------------------------------------

OK，以上，已经实现了TextView的自定义，下面我们看看怎么来引用它（以ListView为例）

③在layout文件夹下创建list item 的布局规定：

todolist_item.xml

xml version="1.0" encoding="utf-8"?>
<com.yinger.TodoListItemView
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:padding="10dp"
  android:scrollbars="vertical"
  android:textColor="@color/notepad_text"
  android:fadingEdge="vertical"
/>

注意，黄色部分是重点。

④大家熟悉的布局文件，我这里是main.xml，没啥好说的。

xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
  <EditText
    android:id="@+id/myEditText"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="New To Do Item"
  />
  <ListView
    android:id="@+id/myListView"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
  />
LinearLayout>

⑤和以前一样的定义ListView，没啥区别：

package com.yinger;

import java.util.ArrayList;

import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnKeyListener;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;

public class TextViewDemo extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

     // Get references to UI widgets
        ListView myListView = (ListView)findViewById(R.id.myListView);
        final EditText myEditText = (EditText)findViewById(R.id.myEditText);

        final ArrayList<String> todoItems = new ArrayList<String>();
        int resID = R.layout.todolist_item;
        final ArrayAdapter<String> aa = new ArrayAdapter<String>(this, resID,
                                                                 todoItems);
        myListView.setAdapter(aa);

        myEditText.setOnKeyListener(new OnKeyListener() {
            public boolean onKey(View v, int keyCode, KeyEvent event) {
              if (event.getAction() == KeyEvent.ACTION_DOWN)
                if (keyCode == KeyEvent.KEYCODE_DPAD_CENTER)
                {
                  todoItems.add(0, myEditText.getText().toString());
                  aa.notifyDataSetChanged();
                  myEditText.setText("");
                  return true;
                }
              return false;
            }
          });
    }
}

运行结果截图：

Ying-er 2011-06-11 21:26 发表评论

android中可以使用标签来创建样式

Ying-er — Mon, 06 Jun 2011 10:43:00 GMT

在values下新建一个styles.xml文件：

xml version="1.0" encoding="utf-8"?>
<resources>
  <style name="ToDoTheme" parent="@android:style/Theme.Black">
    <item name="android:textSize">12spitem>
  style>
resources>

在manifest中引用该样式：

xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.paad.todolist"
  android:versionCode="1"
  android:versionName="1.0">
  <application android:icon="@drawable/icon" android:label="@string/app_name" android:debuggable="True">
    <activity
      android:name=".ToDoList"
      android:label="@string/app_name"
      android:theme="@style/ToDoTheme">
      <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
      intent-filter>
    activity>
  application>
  <uses-sdk android:minSdkVersion="7" />
manifest>

此外，多说一嘴：不知读者住没注意到样式支持通过在标签上使用parent属性来进行继承（见绿色部分）

注：本文参考《android 2 高级编程》一书

标签上使用parent属性来进行继承（见绿色区域）注：本文参考《android 2 高级编程》一书

Ying-er 2011-06-06 18:43 发表评论

android 的尺寸单位

Ying-er — Mon, 06 Jun 2011 04:58:00 GMT

①px（屏幕像素）

②in （物理英寸）

③mm（物理毫米）

④dp（相对于160-dip（dots per inch）的屏幕的非密度制约的像素）

⑤sp（缩放比例无关（Scale-independent）的像素）

PS：我一般用dp和sp -。-

Ying-er 2011-06-06 12:58 发表评论

Android requires .class compatibility set to 5.0. Please fix project properties.

Ying-er — Mon, 06 Jun 2011 04:50:00 GMT

解决办法：

工程上右键-->Android Tools-->Fix Project Properties

然后rebuild

Ying-er 2011-06-06 12:50 发表评论

【工具类】获取android手机联系人的名子和号码，并以List的形式返回

Ying-er — Thu, 26 May 2011 02:05:00 GMT

package yinger.firewall.util;

import java.util.ArrayList;
import java.util.HashMap;

import android.content.ContentResolver;
import android.content.Context;
import android.database.Cursor;
import android.provider.ContactsContract;
import android.provider.ContactsContract.PhoneLookup;

/**
* ReadContactsUtil
*
* @author Ying_er
* @Email melody.crazycoding@gmail.com
* @time 2011/03/30 11:57:23
* @version 1.00
*/
public final class MyReadContactsUtil {
    /**
     * @return contacts list
     */
    public static ArrayList getContacts(Context context) {
        ArrayList<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>();
        String number = "";
        ContentResolver cr = context.getContentResolver();// 得到一个ContentResolver对象
        // 得到一个游标查询对象
        Cursor cursor = cr.query(ContactsContract.Contacts.CONTENT_URI, null,
                null, null, null);
        while (cursor.moveToNext()) {
            // 获取联系人的名字的索引
            int nameFieldColumnIndex = cursor
                    .getColumnIndex(PhoneLookup.DISPLAY_NAME);
            // 获取联系人的名字
            String contact = cursor.getString(nameFieldColumnIndex);
            Cursor target = context.getContentResolver().query(
                    ContactsContract.Contacts.CONTENT_URI, null, null, null,
                    null);
            target.moveToFirst();
            // 得到联系人的ID
            String contentId = cursor.getString(target
                    .getColumnIndex(ContactsContract.Contacts._ID));
            String isPnone = cursor
                    .getString(cursor
                            .getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER));
            if (Integer.parseInt(isPnone) > 0) {
                Cursor phone = context.getContentResolver().query(
                        ContactsContract.CommonDataKinds.Phone.CONTENT_URI,
                        null,
                        ContactsContract.CommonDataKinds.Phone.CONTACT_ID + "="
                                + contentId, null, null);
                while (phone.moveToNext()) {
                    // 得到联系人电话
                    number = phone
                            .getString(phone
                                    .getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
                    HashMap<String, String> map = new HashMap<String, String>();
                    map.put("number", number);
                    map.put("name", contact);
                    number = "";
                    list.add(map);
                }
                phone.close();
            }
        }
        cursor.close();
        return list;
    }
}

Ying-er 2011-05-26 10:05 发表评论

还在用递归删除文件夹及里面的文件吗？android下一行命令搞定！

Ying-er — Wed, 25 May 2011 03:31:00 GMT

/**
     * delete Memory APP_ROOT (menus)
     */
    private void deleteMemoryRoot() {
        try {
            Runtime.getRuntime().exec(
                    "rm -r " + fileUtils.getCurrentRoot() + APP_ROOT);
            try {
                Thread.sleep(500);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

注：刚刚执行完此命令后，android很疲惫，需要睡一会儿，否则再对此路径做文件操作会报错——这才是我最想说的。。。

Ying-er 2011-05-25 11:31 发表评论

使用PreferenceActivity时，如何获取ListPreference中选中的值

Ying-er — Tue, 05 Apr 2011 07:47:00 GMT

汗~~~研究了一天，貌似ListPreference中根本就没有什么回调函数可以用
于是，向上一层，把注意力集中于SharedPreferences，
发现有这么个接口：onSharedPreferenceChanged
抱着试试看的态度，实现了该接口，发现此方法可行，先将部分代码分享如下：

package yinger.firewall;

import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.os.Bundle;
import android.preference.CheckBoxPreference;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceActivity;
import android.preference.PreferenceManager;
import android.preference.PreferenceScreen;

public class CallFireWall extends PreferenceActivity implements
        OnSharedPreferenceChangeListener {
    ListPreference lp = null;
    String whiteMode = "1";
    String blackMode = "2";

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);
        this.setTitle("Ying_er" + "  Call Safe");
        SharedPreferences prefs = PreferenceManager
                .getDefaultSharedPreferences(this);
        prefs.registerOnSharedPreferenceChangeListener(this);
        lp = (ListPreference) findPreference(getString(R.string.pref_mode_key));
    }

    @Override
    public boolean onPreferenceTreeClick(PreferenceScreen preferenceScreen,
            Preference preference) {
        // TODO Auto-generated method stub
        return super.onPreferenceTreeClick(preferenceScreen, preference);
    }

    @Override
    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,
            String key) {
        // TODO Auto-generated method stub
        System.out.println("onSharedPreferenceChanged");
        if (key == getString(R.string.pref_mode_key)){
            System.out.println(lp.getValue());
            if(lp.getValue().equals(whiteMode)){

            }
        }
    }
}

注意：该事件需要注册。既：

prefs.registerOnSharedPreferenceChangeListener(this);

Ying-er 2011-04-05 15:47 发表评论

generating final archive: Debug Certificate expired on 11-3-27 下午3:05 MyMp3Player Unknown Android Packaging Problem

Ying-er — Sun, 27 Mar 2011 09:55:00 GMT

今天新建项目时突然提示：
Error generating final archive: Debug Certificate expired on 11-3-27 下午3:05 MyMp3Player Unknown Android Packaging Problem
而且项目上有个小红叉
原因：Google官方给出了解决办法：

To fix this problem, simply delete the debug.keystore file. The default storage location for AVDs is in ~/.android/avd on OS X and Linux, in C:\Documents and Settings\\.android\ on Windows XP, and in C:\Users\\.android\ on Windows Vista.

The next time you build, the build tools will regenerate a new keystore and debug key

也就是删掉.android文件夹下的debug.keystore文件，然后重新build一下获取新的debug.keystore。这样新建项目时就正常了。
我表示很囧。

Ying-er 2011-03-27 17:55 发表评论

java.net.ConnectException: Connection 127.0.0.1:8080 refused

Ying-er — Sun, 13 Mar 2011 12:36:00 GMT

在使用android内置的模拟器访问本地机器上的资源时会报该错误
原因：模拟器把自己当成主机了，即，将127.0.0.1指向了自己
解决办法：android有个内置的ip：10.0.22，使用该ip来访问本地机器
既：
将原url：http://localhost:8080/androidLoadTest/web/test.txt
改为：http://10.0.2.2:8080/androidLoadTest/web/test.txt

Ying-er 2011-03-13 20:36 发表评论

ERROR: the user data image is used by another emulator. aborting

Ying-er — Sun, 13 Mar 2011 12:14:00 GMT

原因：上次没有正常关闭该模拟器，模拟器被锁定，占用着资源
解决办法：打开 C:/Documents and Settings/users/.android/avd/你所使用的模拟器名称
删去以.lock结尾的文件夹即可

Ying-er 2011-03-13 20:14 发表评论

即使HelloWorld也 java.lang.NullPointerException at com.android.ddmlib.Client.sendAndConsume(Client.java:572)

Ying-er — Wed, 09 Mar 2011 08:16:00 GMT

[2011-03-09 15:39:23 - ddms]null
java.lang.NullPointerException
    at com.android.ddmlib.Client.sendAndConsume(Client.java:572)
    at com.android.ddmlib.HandleHello.sendHELO(HandleHello.java:142)
    at com.android.ddmlib.HandleHello.sendHelloCommands(HandleHello.java:65)
    at com.android.ddmlib.Client.getJdwpPacket(Client.java:671)
    at com.android.ddmlib.MonitorThread.processClientActivity(MonitorThread.java:317)
    at com.android.ddmlib.MonitorThread.run(MonitorThread.java:263)

[2011-03-09 15:39:23 - ddms]null
java.lang.NullPointerException
    at com.android.ddmlib.Client.sendAndConsume(Client.java:572)
    at com.android.ddmlib.HandleHello.sendHELO(HandleHello.java:142)
    at com.android.ddmlib.HandleHello.sendHelloCommands(HandleHello.java:65)
    at com.android.ddmlib.Client.getJdwpPacket(Client.java:671)
    at com.android.ddmlib.MonitorThread.processClientActivity(MonitorThread.java:317)
    at com.android.ddmlib.MonitorThread.run(MonitorThread.java:263)

具体原因不明，但修改下AVD SDCard的Size就OK了。囧死。

Ying-er 2011-03-09 16:16 发表评论

android平台架构模型

Ying-er — Fri, 05 Nov 2010 01:14:00 GMT

PS：
Application framework: 可重用的和可替换的组件部分，在这个层面上，所有的软件都是平等的。
Dalvik virtul machine: 一个基于Linux的虚拟机。
Integrated browser: 一个基于开源的WebKit引擎的浏览器，在应用程序层。
Optimized graphics: 包含一个自定义的2D图形库和基于OpenGL ES 1.0 标准的3D实现。
SQLite: 数据库
Media support: 通用的音频，视频和对各种图片格式的支持(MPEG4, H.264, MP3, AAC, AMR, JPG, PNG, GIF)
GSM Telephony: GSM 移动网络, 硬件支持。
Bluetooth, EDGE, 3G, and WiFi: 都依赖于硬件支持。
Camera, GPS, compass, and accelerometer: 都依赖于硬件支持。
Rich development environment: 包含一套完整的开发工具集，方便跟踪调试，内存检测和性能测试，而且提供了Eclipse的插件。

Ying-er 2010-11-05 09:14 发表评论

android Installed Packages时 Faild to fetch URL

Ying-er — Thu, 09 Sep 2010 02:14:00 GMT

解决办法：
http://www.android123.com.cn/zhongwensdk/366.html

Ying-er 2010-09-09 10:14 发表评论

……is missing required source folder gen

Ying-er — Sat, 27 Mar 2010 08:14:00 GMT

Eclipse3.5.2 + Android ADT2.1
创建新的Android项目后总是提示错误：Project ... is missing required source folder: 'gen'。
解决办法:将Eclipse自动生成的R.java删掉，刷新项目，R.java便会重新生成

Ying-er 2010-03-27 16:14 发表评论