java - 从手机中选择图片并通过单击按钮将其设置为壁纸的活动

Question

这是一个活动文件，可帮助用户从移动设备中选择图像。然后将其设置为墙纸，但是当我选择图像时，我的手机墙纸没有任何反应。我还在清单文件中创建了一个权限。它似乎一直在工作，直到我在手机中打开一个窗口来选择图像，但在那之后它只是工作但不改变壁纸。错误应该在 onActivityResult 方法中。

代码：包com.example.android.mca3project；

    import android.app.Activity;
    import android.app.WallpaperManager;
    import android.content.Intent;
    import android.graphics.Bitmap;
    import android.graphics.BitmapFactory;
    import android.os.Bundle;
    import android.support.v7.app.AppCompatActivity;
    import android.support.v7.widget.Toolbar;
    import android.view.View;
    import android.widget.Toast;

    import java.io.FileNotFoundException;
    import java.io.IOException;
    import java.io.InputStream;

    public class Main2Activity extends AppCompatActivity {
        private static final int PICK_IMAGE = 0;
        InputStream inputStream;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main2);
            Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
            setSupportActionBar(toolbar);


        }

        public void selectimagemethod(View view) {
            Intent intent = new Intent();
            intent.setType("image/*");
            intent.setAction(Intent.ACTION_GET_CONTENT);
            startActivityForResult(Intent.createChooser(intent, "Select Picture"), PICK_IMAGE);
        }

        @Override
        public void onActivityResult(int requestCode, int resultCode, Intent data) {
            super.onActivityResult(requestCode, resultCode, data);
            if (requestCode == PICK_IMAGE && resultCode == Activity.RESULT_OK) {
                if (data == null) {
                    //Display an error
                    return;
                }
                try {
                    inputStream = this.getContentResolver().openInputStream(data.getData());
                } catch (FileNotFoundException e) {
                    Toast.makeText(getApplicationContext(), "Error! Image not found.", Toast.LENGTH_LONG).show();
                }
                Bitmap bm = BitmapFactory.decodeStream(inputStream);
                //Now you can do whatever you want with your inpustream, save it as file, upload to a server, decode a bitmap...
                WallpaperManager myWallpaperManager
                        = WallpaperManager.getInstance(getApplicationContext());
                try {
                    myWallpaperManager.setBitmap(bm);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }


        }
    }

在没有过滤器的情况下向上滚动很多之后出现 Logcat 错误我发现了这些：我可以看到 SETWALLPAPER 权限存在某种问题。

11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime: FATAL EXCEPTION: main
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime: Process: com.example.android.mca3project, PID: 12150
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime: java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=0, result=-1, data=Intent { dat=content://com.android.providers.media.documents/document/image:61 flg=0x1 }} to activity {com.example.android.mca3project/com.example.android.mca3project.Main2Activity}: java.lang.SecurityException: Access denied to process: 12150, must have permission android.permission.SET_WALLPAPER
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.deliverResults(ActivityThread.java:3588)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.handleSendResult(ActivityThread.java:3631)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.access$1300(ActivityThread.java:151)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1359)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:102)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5268)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:902)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:697)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:  Caused by: java.lang.SecurityException: Access denied to process: 12150, must have permission android.permission.SET_WALLPAPER
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.os.Parcel.readException(Parcel.java:1546)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.os.Parcel.readException(Parcel.java:1499)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.IWallpaperManager$Stub$Proxy.setWallpaper(IWallpaperManager.java:218)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.WallpaperManager.setBitmap(WallpaperManager.java:755)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at com.example.android.mca3project.Main2Activity.onActivityResult(Main2Activity.java:57)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.Activity.dispatchActivityResult(Activity.java:6235)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.deliverResults(ActivityThread.java:3584)
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.handleSendResult(ActivityThread.java:3631) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.access$1300(ActivityThread.java:151) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1359) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:102) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5268) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:902) 
11-09 23:44:13.653 12150-12150/com.example.android.mca3project E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:697) 

这是我的清单文件：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.android.mca3project" >

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <uses-permission android:name="android.permission.SET_WALLPAPER"/>
        <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
        <activity
            android:name=".MainActivity"
            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=".Main2Activity"
            android:label="@string/title_activity_main2"
            android:parentActivityName=".MainActivity"
            android:theme="@style/AppTheme.NoActionBar" >
            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value="com.example.android.mca3project.MainActivity" />
        </activity>
    </application>

</manifest>

Answer 1

你的清单是错误的。让它像这样：

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

 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.android.mca3project" >

<uses-permission android:name="android.permission.SET_WALLPAPER"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >

    <activity
        android:name=".MainActivity"
        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=".Main2Activity"
        android:label="@string/title_activity_main2"
        android:parentActivityName=".MainActivity"
        android:theme="@style/AppTheme.NoActionBar" >
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value="com.example.android.mca3project.MainActivity" />
    </activity>
</application>