悬浮按钮

FloatingActionButton 悬浮按钮

悬浮按钮时DesignSupport库的一个控件，可以帮助我们轻松实现悬浮按钮的功能。

Snackbar 可交互提示条

Toast不能交互，仅提供展示，Snackbar可交互。

Snackbar.make(v, "Clicked It", Snackbar.LENGTH_LONG)
    .setAction("Click", new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Toast.makeText(FloatingActionButtonActivity.this,
                "Clicked FloatingActionButton then Clicked Snackbar",
                Toast.LENGTH_LONG).show();
            }
    }).show();

CoordinatorLayout

是一个加强版的FrameLayout，它可以监控子控件的各种事件，帮助我们做出最合理的响应。
如snackbar弹出，FloatingActionButton位置自动跟随上移，不被遮挡。

示例代码

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activity_floating_action_button.xml

<android.support.v4.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/dl_fab">

    <android.support.design.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <android.support.design.widget.FloatingActionButton
            android:id="@+id/fab_btn_1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|end"
            android:layout_margin="16dp"
            android:src="@drawable/ic_launcher_background"
            android:elevation="8dp" />
    </android.support.design.widget.CoordinatorLayout>
</android.support.v4.widget.DrawerLayout>

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FloatingActionButton.java

public class FloatingActionButtonActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_floating_action_button);

        DrawerLayout layout = findViewById(R.id.dl_fab);
        FloatingActionButton btn = findViewById(R.id.fab_btn_1);
        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Snackbar.make(v, "Clicked It", Snackbar.LENGTH_LONG)
                        .setAction("Click", new View.OnClickListener() {
                            @Override
                            public void onClick(View v) {
                                Toast.makeText(FloatingActionButtonActivity.this,
                                        "Clicked FloatingActionButton then Clicked Snackbar",
                                        Toast.LENGTH_LONG).show();
                            }
                        }).show();
            }
        });
    }
}

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