Question

在我的Android应用程序中，我正在使用选项卡内的活动组，同时维护以前屏幕的列表。问题是，如果我们在屏幕加载后立即按回，则不会调用Backpress方法并且应用程序获取退出，但如果我在屏幕上延迟说30秒后也按预期工作，它按预期工作。根本无法解决问题。已调试代码并注意到新屏幕已添加到堆栈列表但背景方法它本身没有被调用。在活动中以及tabgroup类中实现了反向操作但没有用。请让我知道我哪里出错了。我用来添加活动的代码是

Intent intent = new Intent(context, TrialActivity.class);
intent.putExtra("feedId", moreitems.get(arg2).getItem_id());
intent.putExtra("heading", moreitems.get(arg2).getItem_name());
TabGroupActivity parentActivity = (TabGroupActivity) ((Activity) context)
                    .getParent();
 parentActivity.startChildActivity(moreitems.get(arg2).getItem_name()
            + Calendar.getInstance().getTimeInMillis(), intent);

MyTabgroup类是

@SuppressWarnings("deprecation")
public class TabGroupActivity extends ActivityGroup {

    private ArrayList<String> mIdList;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (mIdList == null)
            mIdList = new ArrayList<String>();
    }
    @Override
    protected void onPause()
    {
        super.onPause();
    }

    @Override
    protected void onResume() {
        // to start the first activity every time on reload( on focus of tab).

        // remove the search activity if it is in the stack
        if (mIdList != null && mIdList.size() > 0) {
            int index = -1;
            for (int i = 0; i < mIdList.size(); i++) {
                String firstId = mIdList.get(i);
                if (firstId != null
                        && "search".equalsIgnoreCase(firstId.substring(0,
                                firstId.length() - 1))) {
                    index = i;
                }

            }
            if (index != -1) {
                LocalActivityManager manager = getLocalActivityManager();
                manager.destroyActivity(mIdList.get(index), true);
                mIdList.remove(index);
                index--;
                String lastId = mIdList.get(index);

                Intent lastIntent = manager.getActivity(lastId).getIntent();

                Window newWindow = manager.startActivity(lastId, lastIntent);
                setContentView(newWindow.getDecorView());
            }

        }
        super.onResume();
    }



    /**
     * This is called when a child activity of this one calls its finish method.
     * This implementation calls {@link LocalActivityManager#destroyActivity} on
     * the child activity and starts the previous activity. If the last child
     * activity just called finish(),this activity (the parent), calls finish to
     * finish the entire group.
     */

    @Override
    public void finishFromChild(Activity child) {

        LocalActivityManager manager = getLocalActivityManager();
        int index = mIdList.size() - 1;

        if (index < 1) {
            Alerts.exit("Confirm",
                    "Do you really wish to exit from iDream Media?", this);
            return;
        }

        manager.destroyActivity(mIdList.get(index), true);
        mIdList.remove(index);
        index--;
        String lastId = mIdList.get(index);
        Intent lastIntent = manager.getActivity(lastId).getIntent();

        Window newWindow = manager.startActivity(lastId, lastIntent);
        setContentView(newWindow.getDecorView());
    }

    /**
     * Starts an Activity as a child Activity to this.
     * 
     * @param Id
     *            Unique identifier of the activity to be started.
     * @param intent
     *            The Intent describing the activity to be started.
     * @throws android.content.ActivityNotFoundException.
     */
    public void startChildActivity(String Id, Intent intent) {

        Window window = getLocalActivityManager().startActivity(Id,
                intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP));
        if (window != null) {
            mIdList.add(Id);
            setContentView(window.getDecorView());
        }
    }

    /**
     * The primary purpose is to prevent systems before
     * android.os.Build.VERSION_CODES.ECLAIR from calling their default
     * KeyEvent.KEYCODE_BACK during onKeyDown.
     */
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            // onBackPressed();
            // preventing default implementation previous to
            // android.os.Build.VERSION_CODES.ECLAIR
            return true;
        }
        return super.onKeyDown(keyCode, event);
    }

    /**
     * Overrides the default implementation for KeyEvent.KEYCODE_BACK so that
     * all systems call onBackPressed().
     */
    @Override
    public boolean onKeyUp(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            onBackPressed();
            return true;
        }
        return super.onKeyUp(keyCode, event);
    }

    /**
     * If a Child Activity handles KeyEvent.KEYCODE_BACK. Simply override and
     * add this method.
     */
    @Override
    public void onBackPressed() {
        int length = mIdList.size();
        if (length > 1) {
            Activity current = getLocalActivityManager().getActivity(
                    mIdList.get(length - 1));
            current.finishFromChild(current);
        }
    }

}

请让我知道我哪里出错。

Answer 1

我终于发现问题是因为广告显示在标签页面上。请参阅以下链接并解决了问题。 Back button behavior with tabs and ActivityGroup

backpress未在活动组内部调用android

1 个答案: