Android SnackBar

public class MainActivity extends Activity {  
    private SnackBar mSnackBar;  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
        mSnackBar = new SnackBar.Builder(this)  
        .withMessage("提示信息")  
        .withDuration(SnackBar.LONG_SNACK)  
        .show();  
    }  
  
}  

分享个退出提示工具类DoubleClickExitHelper.java
package miuyongjun.twentysix.utils;


import android.app.Activity;
import android.os.Handler;
import android.os.Looper;
import android.support.design.widget.Snackbar;
import android.view.KeyEvent;
import android.view.View;

/**
 * 双击退出工具类
 *
 * @author wxc
 */
public class DoubleClickExitHelper {

    private final Activity mActivity;

    private boolean isOnKeyBacking;
    private Handler mHandler;
    private Snackbar snackbar;

    public DoubleClickExitHelper(Activity activity) {
        mActivity = activity;
        mHandler = new Handler(Looper.getMainLooper());
        AppManager.getAppManager().addActivity(mActivity);
    }

    /**
     * Activity onKeyDown事件
     */
    public boolean onKeyDown(int keyCode, View view) {
        if (keyCode != KeyEvent.KEYCODE_BACK) {
            return false;
        }
        if (isOnKeyBacking) {
            mHandler.removeCallbacks(onBackTimeRunnable);
            if (snackbar != null) {
                snackbar.dismiss();
            }
            AppManager.getAppManager().AppExit(mActivity);
            return true;
        } else {
            isOnKeyBacking = true;
            if (snackbar == null) {
                snackbar = Snackbar.make(view, "再次点击退出应用", 2000);
            }
            snackbar.show();
            mHandler.postDelayed(onBackTimeRunnable, 2000);
            return true;
        }
    }

    private Runnable onBackTimeRunnable = new Runnable() {
        @Override
        public void run() {
            isOnKeyBacking = false;
            if (snackbar != null) {
                snackbar.dismiss();
            }
        }
    };
}

<pre code_snippet_id="1703141" snippet_file_name="blog_20160531_2_7463231" style="background-color:#2b2b2b;color:#a9b7c6;font-family:‘Source Code Pro‘;font-size:10.5pt;"><span style="color:#bbb529;">@Override
</span><span style="color:#cc7832;">public boolean </span><span style="color:#ffc66d;">onKeyDown</span>(<span style="color:#cc7832;">int </span>keyCode<span style="color:#cc7832;">, </span>KeyEvent event) {
    <span style="color:#cc7832;">boolean </span><span style="color:#68b5ee;">flag </span>= <span style="color:#cc7832;">true;
</span><span style="color:#cc7832;">    if </span>(keyCode == KeyEvent.<span style="color:#9876aa;"><em>KEYCODE_BACK</em></span>) {
        <span style="color:#cc7832;">return </span><span style="color:#9876aa;">mDoubleClickExitHelper</span>.onKeyDown(keyCode<span style="color:#cc7832;">, </span><span style="color:#9876aa;">navigationView</span>)<span style="color:#cc7832;">;
</span><span style="color:#cc7832;">    </span>}
    <span style="color:#cc7832;">return </span><span style="color:#68b5ee;">flag</span><span style="color:#cc7832;">;
</span>}</pre><br>