Android开发中更新UI的几种常用方式

Android开发中，我们经常会头疼UI更新的问题，尤其是跨线程更新UI。今天我们就来聊一聊具体有哪些能够可靠更新UI的的方式：
1、EventBus更新UI：该方式几乎没有使用环境限制，且是线程安全的。不足之处是内部通过主解实现的，有一点点影响效率；
2、RunOnUiThread更新UI：是Activity中的方法，在线程中我们需要告诉系统是哪个activity调用，所以需要在前面指明调用的activity，亦即：***Activity.this.runOnUiThread()。可以说是专门为在子线程中更新UI设计的而且高效;
3、Handller更新UI：也是一种跨线程更新UI的方式，与EventBus一样，几乎可以在所有场合使用，在使用上稍微有一点繁琐；
4、Interface接口回调更新UI：比较常用的一种更新方式，局限性在于：只能直接用在主线程中；
5、runOnUiThread + EventBus更新UI：前面方式1和2的组合；
6、runOnUiThread + Interface接口：前面方式2和4的组合；
7、子线程 + runOnUiThread + Interface接口更新UI；
8、子线程 + EventBus更新UI。

其中常用的应该是前面3中。具体用法如下：

xml中布局：

<RelativeLayout    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_thread"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context="com.haoyue.demo_list.thread.ThreadActivity">    <TextView        android:id="@+id/tvTextThread"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentBottom="true"        android:layout_marginBottom="20dp"        android:layout_centerInParent="true"        android:text="UI更新"        android:textSize="16sp"/>    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="vertical">        <Button            android:id="@+id/btChildThreadEventBus"            android:layout_width="wrap_content"            android:layout_height="50dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="子线程new Thread + EventBus更新UI"            android:textAllCaps="false"/>        <Button            android:id="@+id/btChildThread_RunOnUiThread_Inter"            android:layout_width="wrap_content"            android:layout_height="50dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="子线程 → runOnUiThread →Interface接口更新UI"            android:textAllCaps="false"/>        <Button            android:id="@+id/btRunOnUiThread_Inter"            android:layout_width="wrap_content"            android:layout_height="50dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="runOnUiThread线程 → Interface接口更新UI"            android:textAllCaps="false"/>        <Button            android:id="@+id/btRunOnUiThread_EventBus"            android:layout_width="wrap_content"            android:layout_height="50dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="runOnUiThread + EventBus更新UI"            android:textAllCaps="false"/>        <Button            android:id="@+id/btUpdateUI_Handller"            android:layout_width="wrap_content"            android:layout_height="50dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="通过Handller测试接口回调更新UI"            android:textAllCaps="false"/>        <Button            android:id="@+id/btUpdateUI_EventBus"            android:layout_width="wrap_content"            android:layout_height="50dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="通过EventBus测试子线程回调接口更新UI"            android:textAllCaps="false"/>        <Button            android:id="@+id/btRunOnUiThread"            android:layout_width="wrap_content"            android:layout_height="50dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="通过RunOnUiThread测试更新UI"            android:textAllCaps="false"/>        <Button            android:id="@+id/btInterface"            android:layout_width="wrap_content"            android:layout_height="40dp"            android:layout_margin="5dp"            android:background="@drawable/button_background"            android:text="通过Interface接口测试更新UI"            android:textAllCaps="false"/>    </LinearLayout></RelativeLayout>

interface接口：

public interface InterfaceThread {    void update(String string);}

Activity代码：

public class ThreadActivity extends AppCompatActivity {    @BindView(tvTextThread)    TextView mTvTextThread;    @BindView(R.id.btChildThreadEventBus)    Button mBtChildThreadEventBus;    @BindView(R.id.btChildThread_RunOnUiThread_Inter)    Button mBtChildThreadRunOnUiThreadInter;    @BindView(R.id.btRunOnUiThread_Inter)    Button mBtRunOnUiThreadInter;    @BindView(R.id.btRunOnUiThread_EventBus)    Button mBtRunOnUiThreadEventBus;    @BindView(R.id.btUpdateUI_Handller)    Button mBtUpdateUIHandller;    @BindView(R.id.btUpdateUI_EventBus)    Button mBtUpdateUIEventBus;    @BindView(R.id.btRunOnUiThread)    Button mBtRunOnUiThread;    @BindView(R.id.btInterface)    Button mBtInterface;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_thread);        ButterKnife.bind(this);        EventBus.getDefault().register(this);    }    InterfaceThread mThread = new InterfaceThread() {        @Override        public void update(String string) {            mTvTextThread.setText(string);        }    };    Handler mHandler = new Handler() {        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            switch (msg.what) {                case 1:                    mTvTextThread.setText("通过Handler更新UI的测试");                    break;            }        }    };    public void onEventMainThread(EventMsg event) {        mTvTextThread.setText(event.string + "\n 灰色");    }    @Override    protected void onDestroy() {        super.onDestroy();        EventBus.getDefault().unregister(this);    }    @OnClick({R.id.btChildThread_RunOnUiThread_Inter, R.id.btInterface,              R.id.btRunOnUiThread_Inter, R.id.btRunOnUiThread_EventBus,              R.id.btUpdateUI_Handller, R.id.btUpdateUI_EventBus,               R.id.btRunOnUiThread, R.id.btChildThreadEventBus})    public void onViewClicked(View view) {        switch (view.getId()) {            case R.id.btChildThreadEventBus:                new Thread(new Runnable() {                    @Override                    public void run() {                        String msg = "子线程 + EventBus更新UI的测试成功";                        EventBus.getDefault().post(new EventMsg(msg));                    }                }).start();                break;            case R.id.btChildThread_RunOnUiThread_Inter:                new Thread(new Runnable() {                    @Override                    public void run() {                        ThreadActivity.this.runOnUiThread(new Runnable() {                            @Override                            public void run() {                                String msg="子线程→runOnUiThread→接口更新";                                mThread.update(msg);                            }                        });                    }                }).start();                break;            case R.id.btRunOnUiThread_Inter:                ThreadActivity.this.runOnUiThread(new Runnable() {                    @Override                    public void run() {                        String msg ="runOnUiThread + Interface接口更新UI";                        mThread.update(msg );                    }                });                break;            case R.id.btRunOnUiThread_EventBus:                ThreadActivity.this.runOnUiThread(new Runnable() {                    @Override                    public void run() {                        String msg = "runOnUiThread + EventBus更新UI";                        EventBus.getDefault().post(new EventMsg(msg));                    }                });                break;            case R.id.btUpdateUI_Handller:                Message msg = new Message();                msg.what = 1;                mHandler.sendMessage(msg);                break;            case R.id.btUpdateUI_EventBus:                String msg = "通过EventBus更新UI的测试成功";                EventBus.getDefault().post(new EventMsg(msg));                break;            case R.id.btRunOnUiThread:                mTvTextThread.setText("通过RunOnUiThread更新UI测试成功");                break;            case R.id.btInterface:                mThread.update("通过Interface接口回调更新UI的测试成功");                break;        }    }}

以上8中更新方式，亲测均能够成功。实际开发中，用的最多的还是前面4中方式，尤其是方式1、3、4三种方式。