我使用ACRA报告应用程序崩溃。我得到了一个视图没有附加到窗口管理器错误消息,并认为我已经通过包装pDialog.dismiss()修复了它;在if语句中:

if (pDialog!=null) 
{
    if (pDialog.isShowing()) 
    {
        pDialog.dismiss();   
    }
}

它减少了我收到的未附加到窗口管理器崩溃的视图数量,但我仍然得到一些,我不确定如何解决它。

错误信息:

java.lang.IllegalArgumentException: View not attached to window manager
at android.view.WindowManagerGlobal.findViewLocked(WindowManagerGlobal.java:425)
at android.view.WindowManagerGlobal.removeView(WindowManagerGlobal.java:327)
at android.view.WindowManagerImpl.removeView(WindowManagerImpl.java:83)
at android.app.Dialog.dismissDialog(Dialog.java:330)
at android.app.Dialog.dismiss(Dialog.java:312)
at com.package.class$LoadAllProducts.onPostExecute(class.java:624)
at com.package.class$LoadAllProducts.onPostExecute(class.java:1)
at android.os.AsyncTask.finish(AsyncTask.java:631)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1046)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:862)
at dalvik.system.NativeStart.main(Native Method)

代码片段:

class LoadAllProducts extends AsyncTask<String, String, String> 
{

    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute() 
    {
        super.onPreExecute();
        pDialog = new ProgressDialog(CLASS.this);
        pDialog.setMessage("Loading. Please wait...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }

    /**
     * getting All products from url
     * */
    protected String doInBackground(String... args) 
    {
        // Building Parameters
        doMoreStuff("internet");
        return null;
    }


    /**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(String file_url) 
    {
         // dismiss the dialog after getting all products
         if (pDialog!=null) 
         {
                if (pDialog.isShowing()) 
                {
                    pDialog.dismiss();   //This is line 624!    
                }
         }
         something(note);
    }
}

清单:

    <activity
        android:name="pagename.CLASS" 
        android:configChanges="keyboard|keyboardHidden|orientation|screenSize|screenLayout"            
        android:label="@string/name" >
    </activity>

为了阻止撞车,我错过了什么?


当前回答

基于@erakitin的答案,但也兼容Android版本< API级别17。不幸的是,Activity.isDestroyed()只支持API级别17以后,所以如果你的目标是一个更老的API级别,就像我一样,你必须自己检查它。还没有得到视图没有附加到窗口管理器异常之后。

示例代码

public class MainActivity extends Activity {
    private TestAsyncTask mAsyncTask;
    private ProgressDialog mProgressDialog;
    private boolean mIsDestroyed;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (condition) {
            mAsyncTask = new TestAsyncTask();
            mAsyncTask.execute();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();

        if (mAsyncTask != null && mAsyncTask.getStatus() != AsyncTask.Status.FINISHED) {
            Toast.makeText(this, "Still loading", Toast.LENGTH_LONG).show();
            return;
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mIsDestroyed = true;

        if (mProgressDialog != null && mProgressDialog.isShowing()) {
            mProgressDialog.dismiss();
        }
    }

    public class TestAsyncTask extends AsyncTask<Void, Void, AsyncResult> {    
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            mProgressDialog = ProgressDialog.show(MainActivity.this, "Please wait", "doing stuff..");
        }

        @Override
        protected AsyncResult doInBackground(Void... arg0) {
            // Do long running background stuff
            return null;
        }

        @Override
        protected void onPostExecute(AsyncResult result) {
            // Use MainActivity.this.isDestroyed() when targeting API level 17 or higher
            if (mIsDestroyed)// Activity not there anymore
                return;

            mProgressDialog.dismiss();
            // Handle rest onPostExecute
        }
    }
}

其他回答

看看准则是如何运作的:

调用异步任务后,异步任务将在后台运行。这是可取的。现在,这个异步任务有一个附加到Activity的进度对话框,如果你问如何查看代码:

pDialog = new ProgressDialog(CLASS.this);

你通过考试了。这是论点的背景。因此Progress对话框仍然附加到活动。

现在考虑一下这个场景: 如果我们尝试使用finish()方法完成活动,当异步任务正在进行时,是您试图访问附加到活动的资源的点,即活动不再存在时的进度条。

因此你得到:

java.lang.IllegalArgumentException: View not attached to the window manager

解决方法:

1)确保对话框在活动结束前被解除或取消。

2)完成活动,只有在对话框被解散后,即异步任务结束。

基于@erakitin的答案,但也兼容Android版本< API级别17。不幸的是,Activity.isDestroyed()只支持API级别17以后,所以如果你的目标是一个更老的API级别,就像我一样,你必须自己检查它。还没有得到视图没有附加到窗口管理器异常之后。

示例代码

public class MainActivity extends Activity {
    private TestAsyncTask mAsyncTask;
    private ProgressDialog mProgressDialog;
    private boolean mIsDestroyed;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (condition) {
            mAsyncTask = new TestAsyncTask();
            mAsyncTask.execute();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();

        if (mAsyncTask != null && mAsyncTask.getStatus() != AsyncTask.Status.FINISHED) {
            Toast.makeText(this, "Still loading", Toast.LENGTH_LONG).show();
            return;
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mIsDestroyed = true;

        if (mProgressDialog != null && mProgressDialog.isShowing()) {
            mProgressDialog.dismiss();
        }
    }

    public class TestAsyncTask extends AsyncTask<Void, Void, AsyncResult> {    
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            mProgressDialog = ProgressDialog.show(MainActivity.this, "Please wait", "doing stuff..");
        }

        @Override
        protected AsyncResult doInBackground(Void... arg0) {
            // Do long running background stuff
            return null;
        }

        @Override
        protected void onPostExecute(AsyncResult result) {
            // Use MainActivity.this.isDestroyed() when targeting API level 17 or higher
            if (mIsDestroyed)// Activity not there anymore
                return;

            mProgressDialog.dismiss();
            // Handle rest onPostExecute
        }
    }
}

这个问题是因为你的活动在调用dismiss函数之前完成了。处理异常,并检查您的ADB日志的确切原因。

/**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(String file_url) {
    try {
         if (pDialog!=null) {
            pDialog.dismiss();   //This is line 624!    
         }
    } catch (Exception e) {
        // do nothing
    }
     something(note);
}

我有办法重现这个异常。 我使用2 AsyncTask。一个人做长任务,另一个人做短任务。在短任务完成后,调用finish()。当长任务完成并调用Dialog.dismiss()时,它崩溃了。 下面是我的示例代码:

public class MainActivity extends Activity {
    private static final String TAG = "MainActivity";
    private ProgressDialog mProgressDialog;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Log.d(TAG, "onCreate");

        new AsyncTask<Void, Void, Void>(){
            @Override
            protected void onPreExecute() {
                mProgressDialog = ProgressDialog.show(MainActivity.this, "", "plz wait...", true);
            }

            @Override
            protected Void doInBackground(Void... nothing) {
                try {
                    Log.d(TAG, "long thread doInBackground");
                    Thread.sleep(20000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

                return null;
            }

            @Override
            protected void onPostExecute(Void result) {
                Log.d(TAG, "long thread onPostExecute");
                if (mProgressDialog != null && mProgressDialog.isShowing()) {
                    mProgressDialog.dismiss();
                    mProgressDialog = null;
                }
                Log.d(TAG, "long thread onPostExecute call dismiss");
            }
        }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);

        new AsyncTask<Void, Void, Void>(){
            @Override
            protected Void doInBackground(Void... params) {
                try {
                    Log.d(TAG, "short thread doInBackground");
                    Thread.sleep(5000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                return null;
            }

            @Override
            protected void onPostExecute(Void aVoid) {
                super.onPostExecute(aVoid);
                Log.d(TAG, "short thread onPostExecute");
                finish();
                Log.d(TAG, "short thread onPostExecute call finish");
            }
        }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.d(TAG, "onDestroy");
    }
}

您可以尝试这样做,并找出解决此问题的最佳方法。 根据我的研究,至少有4种方法可以解决这个问题:

@erakitin的回答:调用isFinishing()来检查活动的状态 @Kapé的回答是:设置flag来检查活动的状态 使用try/catch来处理它。 调用onDestroy()中的AsyncTask.cancel(false)。它将阻止asynctask执行onPostExecute(),而是执行onCancelled()。 注意:onPostExecute()仍然会执行,即使你调用AsyncTask.cancel(false)在旧的Android操作系统,如Android 2.X.X。

你可以选择最适合你的。

重写dismiss()方法,如下所示:

@Override
public void dismiss() {
    Window window = getWindow();
    if (window == null) {
        return;
    }
    View decor = window.getDecorView();
    if (decor != null && decor.getParent() != null) {
        super.dismiss();
    }
}

要重现问题,只需在解散对话框之前完成活动。