android 抽屜關閉時的卡頓

1.from https://developer.android.com/reference/android/support/v4/widget/DrawerLayout.html

DrawerLayout.DrawerListener can be used to monitor the state and motion of drawer views. Avoid performing expensive operations such as layout during animation as it can cause stuttering; try to perform expensive operations during the STATE_IDLE state. DrawerLayout.SimpleDrawerListeneroffers default/no-op implementations of each callback method.

2.具體實現

http://stackoverflow.com/questions/18343018/optimizing-drawer-and-activity-launching-speed

Avoid performing expensive operations such as layout during animation as it can cause stuttering; try to perform expensive operations during the STATE_IDLE state.

Instead of using a Handler and hard-coding the time delay, you can override the onDrawerStateChanged method of ActionBarDrawerToggle (which implements DrawerLayout.DrawerListener), so that you can perform the expensive operations when the drawer is fully closed.

Inside MainActivity,

private class SmoothActionBarDrawerToggle extends ActionBarDrawerToggle {

    private Runnable runnable;

    public SmoothActionBarDrawerToggle(Activity activity, DrawerLayout drawerLayout, Toolbar toolbar, int openDrawerContentDescRes, int closeDrawerContentDescRes) {
        super(activity, drawerLayout, toolbar, openDrawerContentDescRes, closeDrawerContentDescRes);
    }

    @Override
    public void onDrawerOpened(View drawerView) {
        super.onDrawerOpened(drawerView);
        invalidateOptionsMenu();
    }
    @Override
    public void onDrawerClosed(View view) {
        super.onDrawerClosed(view);
        invalidateOptionsMenu();
    }
    @Override
    public void onDrawerStateChanged(int newState) {
        super.onDrawerStateChanged(newState);
        if (runnable != null && newState == DrawerLayout.STATE_IDLE) {
            runnable.run();
            runnable = null;
        }
    }

    public void runWhenIdle(Runnable runnable) {
        this.runnable = runnable;
    }
}

Set the DrawerListener in onCreate:

mDrawerToggle = new SmoothActionBarDrawerToggle(this, mDrawerLayout, mToolbar, R.string.open, R.string.close);
mDrawerLayout.setDrawerListener(mDrawerToggle);

Finally,

private void selectItem(int position) {
    switch (position) {
        case DRAWER_ITEM_SETTINGS: {
            mDrawerToggle.runWhenIdle(new Runnable() {
                @Override
                public void run() {
                    Intent intent = new Intent(MainActivity.this, SettingsActivity.class);
                    startActivity(intent);
                }
            });
            mDrawerLayout.closeDrawers();
            break;
        }
        case DRAWER_ITEM_HELP: {
            mDrawerToggle.runWhenIdle(new Runnable() {
                @Override
                public void run() {
                    Intent intent = new Intent(MainActivity.this, HelpActivity.class);
                    startActivity(intent);
                }
            });
            mDrawerLayout.closeDrawers();
            break;
        }
    }
}