Question

我在AVD中收到消息 - 不幸的是已经停止了，请帮我解决这个错误，我想在android中学到更多但是被这个错误所吸引。

xml代码

    <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ImageView
        android:id="@+id/iv"
        android:layout_width="250dp"
        android:layout_height="250dp"
        android:layout_gravity="center"
        android:src="@drawable/ic_launcher" 
                android:contentDescription="@null"
        />

    <ImageButton
        android:id="@+id/ib"
        android:layout_width="125dp"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:src="@drawable/ic_launcher"
                android:contentDescription="@null"

         />

    <Button
        android:id="@+id/bt"
        android:layout_width="125dp"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="set wallpaper" />

</LinearLayout>

java代码

    package com.example.second;
  public class photo extends Activity implements View.OnClickListener {

    ImageView iv;
    Button bt;
    ImageButton ib;
    Intent i ;
    Bitmap bmp;
    final static int cameraData =0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        intsallttion();
        InputStream is = getResources().openRawResource(R.drawable.ic_launcher);
        bmp = BitmapFactory.decodeStream(is);

    }
    private void intsallttion() {
        // TODO Auto-generated method stub
        iv = (ImageView) findViewById(R.id.iv);
        bt = (Button) findViewById(R.id.bt);
        ib = (ImageButton) findViewById(R.id.ib);

        bt.setOnClickListener(this);
        ib.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch(v.getId()){
        case R.id.bt:
            try {
                getApplicationContext().setWallpaper(bmp);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            break;

        case R.id.ib:
            i = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(i,cameraData);
            break;
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        // TODO Auto-generated method stub
        super.onActivityResult(requestCode, resultCode, data);
        if(resultCode==RESULT_OK){
            Bundle extras = data.getExtras();
            bmp = (Bitmap) extras.get("data");
            iv.setImageBitmap(bmp);
        }
    }

}

mainfest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.second"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="16" />
    <uses-permission android:name="android.permission.SET_WALLPAPER"/>

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >


        <activity
            android:name=".omar"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

                <activity
            android:name=".Menu"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="com.example.second.MENU" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>



          <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="com.example.second.MAIN" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>



          <activity
            android:name=".TextPlay"
            android:label="@string/app_name" >
        </activity>
         <activity
            android:name=".Email"
            android:label="@string/app_name" >
        </activity> 
           <activity
            android:name=".photo"
            android:label="@string/app_name" >
        </activity> 

    </application>

 </manifest>

Answer 1

您忘记添加.xml文件语句，如

setContentView(R.layout.activity_main);

在onCreate()方法中，在此行之后

super.onCreate(savedInstanceState);

由于您忘记添加.xml，您的活动无法获取该组件的详细信息，如ImageView，Button＆amp;的ImageButton。

Answer 2

您在清单中将活动omar定义为第一个午餐的应用程序：

      <activity
                android:name=".omar"
                android:label="@string/app_name" >
                <!-- remove this intent filter if you don't want to lunch this activity first-->
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
      </activity>

您向我们展示了活动photo。

如果你想在这个活动photo吃午饭，你必须像这样更新你的xml：

 <activity
        android:name=".photo"
        android:label="@string/app_name" >
        <!--this intent filter detects which activity to lunch the first-->
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity> 

    <activity
        android:name=".omar"
        android:label="@string/app_name" >
        <!-- you should remove the intent filter from here -->
    </activity>

此外，在java代码中，您必须在onCreat（）中定义布局。所以你的onCreat看起来像：

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    // I am supposing that your xml file is called  activity_photo.xml .
    setContentView(R.layout.activity_photo);
    intsallttion();
   // getRessources() : get the ressorces of your application (present in your /res folder)
   // openRawResource(R.drawable.ic_launcher) : get "ic_launcher" from /drawable and put it in 
   // InputStream
    InputStream is = getResources().openRawResource(R.drawable.ic_launcher); 
   //this line creats you a Bitmap of the picture ic_launcher


    bmp = BitmapFactory.decodeStream(is);

}

回答你的上一条评论：

在ImageView中，您将使用此代码android:src="@drawable/ic_launcher"放置drawable / ic_launcher。这是您的图片视图：

<ImageView
    android:id="@+id/iv"
    android:layout_width="250dp"
    android:layout_height="250dp"
    android:layout_gravity="center"
    android:src="@drawable/ic_launcher" 
            android:contentDescription="@null"
    />

然后通过代码，您将相同的图片放在此ImageView drawable/ic_launcher中，您将其转换为Bitmap并调用bmp。如果您想要查看更改内容，则必须从图像视图中删除此android:src="@drawable/ic_launcher"，然后单击按钮，您将看到图片显示在ImageView中。然后删除这两行代码：InputStream is = getResources().openRawResource(R.drawable.ic_launcher); bmp = BitmapFactory.decodeStream(is); 然后单击按钮，您将看到图片没有出现。结论：这两行是从您的/ res拍摄的照片并将其放入位图中。然后clickListener将此位图放在ImageView中。如果删除它们，单击Listeners将在ImageView中放置一个空的Bitmap。

不幸的是我的应用程序停止了我该怎么办？

2 个答案: