Android UI(SeekBar)详解

目录：
    1.SeekBar的应用场景
    2.SeekBar的简单使用与事件监听
    3.图片资源自定义SeekBar+手机音量调节
    4.xml绘制自定义SeekBar
        
1.SeekBar的应用场景
    SeekBar的主要应用在音乐播放，视频播放，或者对音量调节，屏幕亮度调节的一些操作中，让用户可以手动的去改变相应的值。
    
2.SeekBar的简单使用与事件监听
    1.activity_main.xml
   

 
    2.content_main.xml
  

 
    3.主java类MainActivity.java
   

package com.example.seekbarui;

import android.os.Bundle;
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.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.SeekBar;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    private SeekBar seekBar;
    private TextView textView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //初始化Toolbar
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        //隐藏Actionbar后将toolbar设置上去替换Actionbar
        setSupportActionBar(toolbar);
        //初始化seekbar，TextView
        seekBar = (SeekBar) findViewById(R.id.seekBar);
        textView = (TextView) findViewById(R.id.result);
        //seekbar设置监听
        seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            /*
            * seekbar改变时的事件监听处理
            * */
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                textView.setText("当前进度："+progress+"%");
                Log.d("debug",String.valueOf(seekBar.getId()));
            }
            /*
            * 按住seekbar时的事件监听处理
            * */
            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {
                Toast.makeText(MainActivity.this,"按住seekbar",Toast.LENGTH_SHORT).show();
            }
            /*
            * 放开seekbar时的时间监听处理
            * */
            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                Toast.makeText(MainActivity.this,"放开seekbar",Toast.LENGTH_SHORT).show();
            }
        });

        //浮动button实例化
        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        //设置点击监听
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
    }

    //创建toolbar菜单
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    //toolbar菜单选择监听
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            Toast.makeText(MainActivity.this,item.getTitle(),Toast.LENGTH_LONG).show();
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

  
    4.效果截图

  

3.图片资源自定义SeekBar+手机音量调节
    1.导入滑动块图片(scrubber.png scrubber_focus.png),进度条就直接xml绘制
    2.scrubber_selector.xml

    3.seekbar_layer.xml(进度条绘制)
   

    4.主布局activity_second.xml
   

    5.主布局java类SecondActivity.java    
   

package com.example.seekbarui;

import android.content.Context;
import android.media.AudioManager;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.WindowManager;
import android.widget.SeekBar;
import android.widget.TextView;
import android.widget.Toast;

public class SecondActivity extends AppCompatActivity {
    private SeekBar seekBar;
    private TextView textView;
    private AudioManager audioManager;
    private int currentVolume,maxVolume;
    private int volume=0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
        //初始化seekbar，TextView
        seekBar = (SeekBar) findViewById(R.id.seekBar2);
        //初始化AudioManager
        audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
        //获取系统最大音量值
        maxVolume =audioManager.getStreamMaxVolume(AudioManager.STREAM_SYSTEM);
        //将seekBar的最大进度值设置成系统最大音量
        seekBar.setMax(maxVolume);
        //获取当前音量值
        currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_SYSTEM);
        //设置当前值为进度条当前值
        seekBar.setProgress(currentVolume);

        //初始化Toolbar
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar1);
        //隐藏Actionbar后将toolbar设置上去替换Actionbar
        setSupportActionBar(toolbar);
        //seekbar设置监听
        seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            /*
            * seekbar改变时的事件监听处理
            * */
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                //设置拖动的进度值为系统音量
                audioManager.setStreamVolume(AudioManager.STREAM_SYSTEM,progress,0);
                //获取当前音量
                currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_SYSTEM);
                //设置当前音量
                seekBar.setProgress(currentVolume);
/*                //获取屏幕属性
                WindowManager.LayoutParams layoutParams = getWindow().getAttributes();
                //设置屏幕亮度
                layoutParams.screenBrightness =((float)seekBar.getProgress())/100;
                Log.d("debug",layoutParams.screenBrightness+"");
                Log.d("deb",seekBar.getProgress()+"");
                //更新窗口属性
                getWindow().setAttributes(layoutParams);*/
            }
            /*
            * 按住seekbar时的事件监听处理
            * */
            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {
                Toast.makeText(SecondActivity.this,"按住seekbar",Toast.LENGTH_SHORT).show();
            }
            /*
            * 放开seekbar时的时间监听处理
            * */
            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                Toast.makeText(SecondActivity.this,"放开seekbar",Toast.LENGTH_SHORT).show();
            }
        });
    }

    //创建toolbar菜单
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    //toolbar菜单选择监听
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            Toast.makeText(SecondActivity.this,item.getTitle(),Toast.LENGTH_LONG).show();
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

    6.效果截图

图片分别为更改前系统音量值，Seekbar效果图，更改后系统音量值

4.xml绘制自定义SeekBar
    上面3进度条的绘制已经运用了xml绘制，下面我们就试着xml绘制一下进度条的滑块
    
    1.未按压时的xml绘制scrubber_shape.xml
   

    
    2.按压时的xml绘制scrubber_focus_shape.xml
 

  
    3.效果截图

   

   参考：http://stackoverflow.com/questions/16163215/android-styling-seek-bar