Android Studio [Toast]

ToastActivity.java

package com.xdw.a122;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import com.xdw.a122.util.ToastUtil;

import java.util.zip.Inflater;

public class ToastActivity extends AppCompatActivity {
    private Button mBtnToast1,mBtnToast2,mBtnToast3,mBtnToast4;
    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_toast);
        mBtnToast1=findViewById(R.id.btn_toast_1);
        mBtnToast2=findViewById(R.id.btn_toast_2);
        mBtnToast3=findViewById(R.id.btn_toast_3);
        mBtnToast4=findViewById(R.id.btn_toast_4);
        OnClick onClick=new OnClick();
        mBtnToast1.setOnClickListener(onClick);
        mBtnToast2.setOnClickListener(onClick);
        mBtnToast3.setOnClickListener(onClick);
        mBtnToast4.setOnClickListener(onClick);
    }
    class OnClick implements View.OnClickListener{
        @Override
        public void onClick(View v) {
            switch (v.getId()){
                case R.id.btn_toast_1:
                    Toast.makeText(getApplicationContext(),"Toast",Toast.LENGTH_LONG).show();
                    break;
                case R.id.btn_toast_2:
                    Toast toastCenter =Toast.makeText(getApplicationContext(),"居中Toast",Toast.LENGTH_LONG);
                    toastCenter.setGravity(Gravity.CENTER,0,0);
                    toastCenter.show();
                    break;
                case R.id.btn_toast_3:
                    Toast toastCustom =new Toast(getApplicationContext());
                    LayoutInflater inflater=LayoutInflater.from(ToastActivity.this);  //用来找res/layout/下的xml布局文件，并且实例化
                    View view=inflater.inflate(R.layout.layout_toast,null);     //layout_toast ---set size
                    ImageView imageView=view.findViewById(R.id.iv_toast);
                    TextView textView=view.findViewById(R.id.tv_toast);
                    imageView.setImageResource(R.drawable.back_2);          //选择显示的图片
                    textView.setText("自定义toast");
                    toastCustom.setView(view);
                    toastCustom.setDuration(Toast.LENGTH_LONG);
                    toastCustom.show();                                 //显示
                    break;
                case R.id.btn_toast_4:
                    ToastUtil.showMsg(getApplicationContext(),"包装过的Toast");
                    break;
            }
        }
    }
}

activity_toast.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".ToastActivity"
    android:orientation="vertical">
    <Button
        android:id="@+id/btn_toast_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="默认"/>
    <Button
        android:id="@+id/btn_toast_2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="改变位置"/>
    <Button
        android:id="@+id/btn_toast_3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="带图片"/>
    <Button
        android:id="@+id/btn_toast_4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="ToastUtil"/>

</LinearLayout>

封装的Toast

ToastUtil.java

package com.xdw.a122.util;

import android.content.Context;
import android.widget.Toast;

import com.xdw.a122.ToastActivity;

public class ToastUtil
{
    public static Toast mToast;
    public static void showMsg(Context context,String msg)
    {
        if (mToast == null) {
            mToast = Toast.makeText(context,msg,Toast.LENGTH_LONG);
        }
        else
            {
                mToast.setText(msg);
            }
            mToast.show();
    }
}