Android Material Design Snackbar Example

http://www.androidhive.info/2015/09/android-material-design-snackbar-example/

     Snackbar 是 Material Design 引入的一个很有用的组件，Snackbars 和 Toast 非常的相似，这两者最大的区别是 Snackbars 可以响应用户的交互事件。Snackbars 会显示在屏幕的底部，而且可以被擦除掉 。本章将会简单的介绍一下它的基本用法 。

1. Simple Snackbar

    首先让我们来看一下 Snackbar 的基本代码

    

Snackbar snackbar = Snackbar

         .make(coordinatorLayout,  "Welcome to AndroidHive" , Snackbar.LENGTH_LONG);  

snackbar.show();

    它的 make() 方法接收三个参数，第一个是一个 view 对象，第二个是一个代表 message 的字符串，第三个是用于指定 message 显示的时间长度的 duration 。通常以  CoordinatorLayout 对象作为 view 对象传递给它是最好的，因为它可以为 Snackbar 套上一些特性，如滑动擦除、显示和隐藏时自动移动其它的 widgets（如移动 FloatingActionButton）。在后面的 demo 中你就可以看到 。

2. Snackbar with Action Callback

    我们可以通过 setAction() 方法给 Snackbar 添加事件监听器，以响应用户的操作 。示例代码如下

Snackbar snackbar = Snackbar

         .make(coordinatorLayout,  "Message is deleted" , Snackbar.LENGTH_LONG)

         .setAction( "UNDO" ,  new  View.OnClickListener() {

             @Override

             public void  onClick(View view) {

                 Snackbar snackbar1 = Snackbar.make(coordinatorLayout,  "Message is restored!" , Snackbar.LENGTH_SHORT);

                 snackbar1.show();

             }

         });

 

snackbar.show();

3. Customizing the Snackbar View

    默认的 Snackbar 的 text 的颜色是白色的，背景色为  #323232 ，当然在显示的时候，我们可以改变这些属性，示例代码如下

Snackbar snackbar = Snackbar

         .make(coordinatorLayout,  "No internet connection!" , Snackbar.LENGTH_LONG)

         .setAction( "RETRY" ,  new View.OnClickListener() {

             @Override

             public void onClick(View view) {

             }

         });

 

// Changing message text color

snackbar.setActionTextColor(Color.RED);

 

// Changing action button text color

View sbView = snackbar.getView();

TextView textView = (TextView) sbView.findViewById(android.support.design.R.id.snackbar_text);

textView.setTextColor(Color.YELLOW);

snackbar.show();

4.  Creating New Project

    接下来我们就来创建一个 Project，看看在具体如何使用，这部分很简单

Now we’ll create a simple app to sea the snackbar in action when the app is having a CoordinatorLayout and a FloatingActionButton.

1. In Android Studio, go to File ⇒ New Project and fill all the details required to create a new project.

2. Open build.gradle and add design support library dependency.

com.android.support:design:23.0.1

dependencies {

     compile fileTree(dir:  'libs' , include: [ '*.jar' ])

     compile  'com.android.support:appcompat-v7:23.0.1'

     compile  'com.android.support:design:23.0.1'

}

3. Optionally you can apply the material design theme by following the steps mentioned here.

4. Open the layout file your main activity activity_main.xml and below code. Here you can see I have added the CoordinatorLayout and FloatingActionButton.

< android.support.design.widget.CoordinatorLayout  xmlns:android = "http://schemas.android.com/apk/res/android"

     xmlns:app = "http://schemas.android.com/apk/res-auto"

     xmlns:tools = "http://schemas.android.com/tools"

     android:id = "@+id/coordinatorLayout"

     android:layout_width = "match_parent"

     android:layout_height = "match_parent"

     tools:context = ".MainActivity" >

 

     < android.support.design.widget.AppBarLayout

         android:layout_width = "match_parent"

         android:layout_height = "wrap_content"

         android:theme = "@style/ThemeOverlay.AppCompat.Dark.ActionBar" >

 

         < android.support.v7.widget.Toolbar

             android:id = "@+id/toolbar"

             android:layout_width = "match_parent"

             android:layout_height = "?attr/actionBarSize"

             android:background = "?attr/colorPrimary"

             app:layout_scrollFlags = "scroll|enterAlways"

             app:popupTheme = "@style/ThemeOverlay.AppCompat.Light" />

     </ android.support.design.widget.AppBarLayout >

 

     < LinearLayout

         android:layout_width = "fill_parent"

         android:layout_height = "wrap_content"

         android:orientation = "vertical"

         android:paddingLeft = "20dp"

         android:paddingRight = "20dp"

         app:layout_behavior = "@string/appbar_scrolling_view_behavior" >

 

         < Button

             android:id = "@+id/btnSimpleSnackbar"

             android:layout_width = "fill_parent"

             android:layout_height = "wrap_content"

             android:layout_marginTop = "30dp"

             android:text = "Simple Snackbar" />

 

         < Button

             android:id = "@+id/btnActionCallback"

             android:layout_width = "fill_parent"

             android:layout_height = "wrap_content"

             android:layout_marginTop = "10dp"

             android:text = "With Action Callback" />

 

         < Button

             android:id = "@+id/btnCustomSnackbar"

             android:layout_width = "fill_parent"

             android:layout_height = "wrap_content"

             android:layout_marginTop = "10dp"

             android:text = "Custom Color" />

 

     </ LinearLayout >

 

     < android.support.design.widget.FloatingActionButton

         android:id = "@+id/fab"

         android:layout_width = "wrap_content"

         android:layout_height = "wrap_content"

         android:layout_gravity = "end|bottom"

         android:layout_margin = "16dp"

         android:src = "@android:drawable/ic_dialog_email" />

 

</ android.support.design.widget.CoordinatorLayout >

5 . Now open  MainActivity.java  and make the changes as mentioned below. This activity contains three button click listeners to show the different ways of implementing the snackbar covering the scenarios explained above.

MainActivity.java

import android.graphics.Color;

import android.os.Bundle;

import android.support.design.widget.CoordinatorLayout;

import android.support.design.widget.FloatingActionButton;

import android.support.design.widget.Snackbar;

import android.support.v7.app.AppCompatActivity;

import android.support.v7.widget.Toolbar;

import android.view.View;

import android.widget.Button;

import android.widget.TextView;

 

public  class  MainActivity  extends  AppCompatActivity {

 

     private  Toolbar mToolbar;

     private  CoordinatorLayout coordinatorLayout;

     private  Button btnSimpleSnackbar, btnActionCallback, btnCustomView;

     private  FloatingActionButton fab;

 

     @Override

     protected  void  onCreate(Bundle savedInstanceState) {

         super .onCreate(savedInstanceState);

         setContentView(R.layout.activity_main);

 

         coordinatorLayout = (CoordinatorLayout) findViewById(R.id

                 .coordinatorLayout);

 

         fab = (FloatingActionButton) findViewById(R.id.fab);

 

         mToolbar = (Toolbar) findViewById(R.id.toolbar);

 

         setSupportActionBar(mToolbar);

 

         btnSimpleSnackbar = (Button) findViewById(R.id.btnSimpleSnackbar);

         btnActionCallback = (Button) findViewById(R.id.btnActionCallback);

         btnCustomView = (Button) findViewById(R.id.btnCustomSnackbar);

 

         btnSimpleSnackbar.setOnClickListener( new View.OnClickListener() {

             @Override

             public void onClick(View view) {

                 Snackbar snackbar = Snackbar

                         .make(coordinatorLayout,  "Welcome to AndroidHive" , Snackbar.LENGTH_LONG);

 

                 snackbar.show();

             }

         });

 

         btnActionCallback.setOnClickListener( new View.OnClickListener() {

             @Override

             public void onClick(View view) {

                 Snackbar snackbar = Snackbar

                         .make(coordinatorLayout,  "Message is deleted" , Snackbar.LENGTH_LONG)

                         .setAction( "UNDO" ,  new View.OnClickListener() {

                             @Override

                             public void onClick(View view) {

                                 Snackbar snackbar1 = Snackbar.make(coordinatorLayout,  "Message is restored!" , Snackbar.LENGTH_SHORT);

                                 snackbar1.show();

                             }

                         });

 

                 snackbar.show();

             }

         });

 

         btnCustomView.setOnClickListener( new View.OnClickListener() {

             @Override

             public void onClick(View view) {

                 Snackbar snackbar = Snackbar

                         .make(coordinatorLayout,  "No internet connection!" , Snackbar.LENGTH_LONG)

                         .setAction( "RETRY" ,  new View.OnClickListener() {

                             @Override

                             public void onClick(View view) {

                             }

                         });

 

                 // Changing message text color

                 snackbar.setActionTextColor(Color.RED);

 

                 // Changing action button text color

                 View sbView = snackbar.getView();

                 TextView textView = (TextView) sbView.findViewById(android.support.design.R.id.snackbar_text);

                 textView.setTextColor(Color.YELLOW);

 

                 snackbar.show();

             }

         });

     }

}

Run and test the app.

Demo 下载