[移动开发]2021-09-17 Android 通过Preference打开新的Activity

一、现在需要在settings里面的选项里面Preference中新增一个选项去启动一个Activity。

二、操作步骤

? ? ? 1、在描述preference的xml中添加intent节点,在这个节点中指定你想要启动Activity所在的包名和类名.通过这些属性系统会自动调用指定的Activity。

? ? ? 2、然后在AndroidMenifest.xml中配置这个Activity。

? ? ? 3、SystemUpateActivity.java源码

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.settings;

import android.appwidget.AppWidgetManager;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.UserHandle;
import android.util.Log;
import android.view.LayoutInflater;
import android.widget.CheckBox;

import androidx.appcompat.app.AlertDialog;
import android.app.Activity;
import android.view.View;

import com.android.internal.app.AlertActivity;
import com.android.internal.app.AlertController;

import android.widget.Toast;
import java.io.IOException;
import com.android.settings.R;


/**
 * This activity is displayed when an app launches the BIND_APPWIDGET intent. This allows apps
 * that don't have the BIND_APPWIDGET permission to bind specific widgets.
 */
public class SystemUpateActivity extends Activity  {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.update_system);
		getActionBar().setTitle("System Upate");
    }


    public  void onClick(View v) {
        // TODO Auto-generated method stub
		if (v.getId() == R.id.recovery)
        {
            Toast.makeText(this, "ready to reboot", Toast.LENGTH_SHORT).show();
            RunCommand("reboot recovery ");
        }
    }
    public  static String RunCommand(String cmd) {
        try {
            Runtime runtime = Runtime.getRuntime();
            Process proc = runtime.exec(cmd);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return  cmd;
    }
}

? ? 4、update_system.xml文件代码

<?xml version="1.0" encoding="utf-8"?>
<!--
  Copyright (C) 2017 The Android Open Source Project

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  -->

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center_horizontal"
    android:paddingTop="50dip"
    android:orientation="horizontal">
    <Button
        android:id="@+id/recovery"
        android:layout_width="350dp"
        android:layout_height="100dp"
        android:text="Reboot to enter recovery"
        android:onClick="onClick"
        />
</LinearLayout>

? ? 5、整个过程修改的文件

? ? 6、真机测试效果图。

?

三、参考文章

Android 通过Preference启动新的Activity_my9074的专栏-CSDN博客