1、点击空白处隐藏软键盘

/*
隐藏软键盘
* */
public boolean dispatchTouchEvent(MotionEvent ev) {
if (ev.getAction() == MotionEvent.ACTION_DOWN) {
View v = getCurrentFocus();
if (isShouldHideInput(v, ev)) {

            InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT\_METHOD\_SERVICE);  
            if (imm != null) {  
                imm.hideSoftInputFromWindow(v.getWindowToken(), 0);  
            }  
        }  
        return super.dispatchTouchEvent(ev);  
    }

    if (getWindow().superDispatchTouchEvent(ev)) {  
        return true;  
    }  
    return onTouchEvent(ev);  
}

public  boolean isShouldHideInput(View v, MotionEvent event) {  
    if (v != null && (v instanceof EditText)) {  
        int\[\] leftTop = { 0, 0 };

        v.getLocationInWindow(leftTop);  
        int left = leftTop\[0\];  
        int top = leftTop\[1\];  
        int bottom = top + v.getHeight();  
        int right = left + v.getWidth();  
        if (event.getX() > left && event.getX() < right  
                && event.getY() > top && event.getY() < bottom) {

        } else {  
            return true;  
        }  
    }  
    return false;  
}

2、沉浸式状态栏

    //设置沉浸式状态栏 android 4.4 及以上支持  

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
//透明状态栏
getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
//透明导航栏
getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
}

3、设置导航栏

xml代码：

<android.support.v7.widget.Toolbar  
    android:id="@+id/toolbar1"  
    android:layout\_width="match\_parent"  
    android:layout\_height="wrap\_content"  
    android:layout\_alignParentLeft="true"  
    android:layout\_alignParentStart="true"  
    android:layout\_alignParentTop="true"  
    android:background="#5caef9"  
    android:minHeight="50dp"  
    android:gravity="center"  
    android:textAlignment="center"  
    >  
</android.support.v7.widget.Toolbar>

后台代码：

    //设置导航栏  
  Toolbar toolbar = (Toolbar)findViewById(R.id.toolbar1);//鑾峰彇椤甸潰鐨勫伐鍏锋爮

    toolbar.setTitle("设置服务");  
    toolbar.setTitleMarginStart(370);  
    toolbar.setTitleTextColor(Color.WHITE);  
    toolbar.setTitleMarginTop(10);  
    toolbar.setNavigationIcon(R.mipmap.allback);  
    toolbar.setNavigationOnClickListener(new View.OnClickListener() {  
        @Override  
        public void onClick(View view) {  
            Intent intent = new Intent(SettingServiceActivity.this,MyselfLoginActivity.class);  
            startActivity(intent);  
        }  
    });

4、获取屏幕宽高和设置控件宽高

    //设置输入框宽高  
    EditText tvservicepath = (EditText)findViewById(R.id.tvservicepath);  
    tvservicepath.setText(R.string.serverpath);//获取资源文件  
    //获取屏幕高宽  
    WindowManager wm = (WindowManager) this.getSystemService(Context.WINDOW\_SERVICE);  
    DisplayMetrics dm = new DisplayMetrics();  
    wm.getDefaultDisplay().getMetrics(dm);  
    int width = dm.widthPixels;         // 屏幕宽度（像素）  
    int height = dm.heightPixels;       // 屏幕高度（像素）  
    float density = dm.density;         // 屏幕密度（0.75 / 1.0 / 1.5）  
    int densityDpi = dm.densityDpi;     // 屏幕密度dpi（120 / 160 / 240）  
    // 屏幕宽度算法:屏幕宽度（像素）/屏幕密度  
    int screenWidth = (int) (width / density);  // 屏幕宽度(dp)  
    int screenHeight = (int) (height / density);// 屏幕高度(dp)

    ViewGroup.LayoutParams para;  
    para = tvservicepath.getLayoutParams();  
    para.height = screenHeight/2;  
    para.width = width-50;  
    tvservicepath.setLayoutParams(para);

5、在手机本地保存数据和读取(参考：https://blog.csdn.net/acm_th/article/details/50009575)

<EditText  
    android:id="@+id/input"  
    android:layout\_width="match\_parent"  
    android:layout\_height="wrap\_content"  
    android:hint="请输入" />

<Button  
    android:id="@+id/btn1"  
    android:layout\_width="match\_parent"  
    android:layout\_height="wrap\_content"  
    android:layout\_below="@+id/input"  
    android:text="保存数据" />

<Button  
    android:id="@+id/btn2"  
    android:layout\_width="match\_parent"  
    android:layout\_height="wrap\_content"  
    android:layout\_below="@+id/btn1"  
    android:text="读取数据"/>

package com.example.savedatademo;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.util.Scanner;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

private Button saveBtn = null;  
private Button readBtn = null;  
private EditText input = null;  
private final static String FILE\_NAME = "xth.txt"; // 设置文件的名称

@Override  
protected void onCreate(Bundle savedInstanceState) {  
    super.onCreate(savedInstanceState);  
    requestWindowFeature(Window.FEATURE\_NO\_TITLE);  
    setContentView(R.layout.activity\_main);

    input = (EditText) findViewById(R.id.input);  
    saveBtn = (Button) findViewById(R.id.btn1);  
    readBtn = (Button) findViewById(R.id.btn2);

    saveBtn.setOnClickListener(new OnClickListener() {  
        @Override  
        public void onClick(View v) {  
            String data = input.getText().toString();  
            save(data);  
            Toast.makeText(MainActivity.this, "保存数据成功！", Toast.LENGTH\_SHORT)  
                    .show();  
        }  
    });  
    readBtn.setOnClickListener(new OnClickListener() {  
        @Override  
        public void onClick(View v) {  
            StringBuffer sb = read();  
            Toast.makeText(MainActivity.this, "读取数据为：" + sb,  
                    Toast.LENGTH\_SHORT).show();  
        }  
    });  
}

private StringBuffer read() {  
    FileInputStream in = null;  
    Scanner s = null;  
    StringBuffer sb = new StringBuffer();  
    try {  
        in = super.openFileInput(FILE\_NAME);  
        s = new Scanner(in);  
        while (s.hasNext()) {  
            sb.append(s.next());  
        }  
    } catch (Exception e) {  
        e.printStackTrace();  
    }  
    return sb;  
}

private void save(String data) {  
    FileOutputStream out = null;  
    PrintStream ps = null;  
    try {  
        out = super.openFileOutput(FILE\_NAME, Activity.MODE\_APPEND);  
        ps = new PrintStream(out);  
        ps.println(data);  
    } catch (Exception e) {  
        e.printStackTrace();  
    } finally {  
        if (out != null) {  
            try {  
                out.close();  
                ps.close();  
            } catch (IOException e) {  
                e.printStackTrace();  
            }  
        }  
    }  
}

}

这是追加内容的，如果覆盖，改成：

out = super.openFileOutput(FILE_NAME, Activity.MODE_WORLD_WRITEABLE);

6、代码设置按钮被点击使用performClick（）方法。

7、设置控件的显示与隐藏：

View缺省为可见的，在应用可以通过setVisibility 修改View的可见性，

View.VISIBLE View可见，View.INVISIBLE View不可以见，但仍然占据可见时的大小和位置。

View.GONE View不可见，且不占据空间。