按钮的启用和禁用学习笔记

xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <Button
            android:id="@+id/btn_enable"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="启用按钮"
            android:textColor="@color/black"
            android:textSize="17sp"></Button>

        <Button
            android:id="@+id/btn_disable"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="禁用按钮"
            android:textColor="@color/black"
            android:textSize="17sp"></Button>
    </LinearLayout>
    <Button
        android:id="@+id/btn_test"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:gravity="center"
        android:text="测试"
        android:textColor="@color/black"
        android:textSize="17sp"></Button>
    <TextView
        android:id="@+id/tv_result"
        android:textColor="#ff00ff"
        android:text="测试"
        android:background="#ffff00"
        android:gravity="center"
        android:layout_width="match_parent"
        android:layout_height="60dp">
    </TextView>

</LinearLayout>

java

package com.example.chapter03;

import androidx.appcompat.app.AppCompatActivity;

import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Button btn_test;
    private TextView tv_result;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_text_view);
        Button btn_enable = findViewById(R.id.btn_enable);
        Button btn_disable = findViewById(R.id.btn_disable);
        btn_test = findViewById(R.id.btn_test);
        tv_result = findViewById(R.id.tv_result);
        btn_enable.setOnClickListener(this);
        btn_disable.setOnClickListener(this);
        btn_test.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.btn_enable:
                btn_test.setEnabled(true);
                btn_test.setTextColor(Color.BLACK);
                break;
            case R.id.btn_disable:
                btn_test.setEnabled(false);
                btn_test.setTextColor(Color.GRAY);
                break;
            case R.id.btn_test:
                String desc = String.format("%s 您点击了按钮：%s", 123, ((Button) view).getText());
                tv_result.setText(desc);
                break;
        }
    }
}