android - 安卓activity无法填充屏幕

新手在开发安卓的过程中遇到了一些问题，在activity的四周总有去不掉的白边 ，activity是没有填满屏幕的，xml里的设置是macthparent没错，不知道问题出在哪里，

补充一下这个界面的xml代码

xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_log_in"
android:layout_width="match_parent"
android:fillViewport="true"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:background="#ffffff"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.administrator.productiontoolforpda.Activity_logIn">=

android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:layout_x="0dp"
android:layout_y="240dp">

java代码

package com.example.administrator.productiontoolforpda;

import android.app.Activity;
import android.app.Dialog;
import android.content.ContentValues;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Color;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;

import java.sql.Date;
import java.text.SimpleDateFormat;

import static com.example.administrator.productiontoolforpda.myApplication.getContext;

public class Activity_logIn extends Dialog {

private EditText account;
private HttpInfo httpInfo;
private EditText password;
private Button ok;
private Button cancel;
private DBHelper dbHelper ;
public static String VERSION = "v1.0";
public  String DEVICE_ID;
public Activity_logIn(Context context){
    super(context,R.style.PopupDialog);

// }

//protected void onCreate(Bundle savedInstanceState) {
   // super.onCreate(savedInstanceState);
    Window win = this.getWindow();
    win.setGravity(Gravity.BOTTOM);                       //从下方弹出
    win.getDecorView().setPadding(0, 0, 0, 0);
    WindowManager.LayoutParams lp = win.getAttributes();
    lp.width = WindowManager.LayoutParams.MATCH_PARENT;   //宽度填满
    lp.height = WindowManager.LayoutParams.WRAP_CONTENT;  //高度自适应
    win.setAttributes(lp);
    super.setContentView(R.layout.activity_log_in);
    account = (EditText)findViewById(R.id.account);
    password = (EditText)findViewById(R.id.password);
    ok = (Button)findViewById(R.id.ok);
    cancel = (Button)findViewById(R.id.cancel);
    TelephonyManager tm = (TelephonyManager)myApplication.getContext().getSystemService(Context.TELEPHONY_SERVICE);
    DEVICE_ID = tm.getDeviceId();
    httpInfo = new HttpInfo();
    dbHelper = new DBHelper(myApplication.getContext());
    //填充登陆账号和密码
    InputUserInfo();
    ok.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String username = account.getText().toString();
            String p = password.getText().toString();
            ContentValues values = new ContentValues();
            //new newThread().start(); //申请产线列表
            httpInfo.lineTest();
            values.put("username",username);
            values.put("password",p);
            dbHelper.deleteFormUser();
            dbHelper.insertIntoUser(values);
            //写入产线信息
            Activity_logIn.this.dismiss();

        }
    });
    cancel.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Activity_logIn.this.dismiss();
        }
    });
}
//测试滚动bar
public void insertLineInfo(){
    for(int i = 0;i<5;i++){
        ContentValues values2 = new ContentValues();
        values2.put("lineNum","未设置产线"+i);
        dbHelper.insertIntoLineNum(values2);
    }
}
public void InputUserInfo(){
    Cursor c = dbHelper.queryFromUser();
    if(c.moveToFirst()) {
        account.setText(c.getString(1));
        password.setText(c.getString(2));
    }
}
class newThread extends Thread{
    public void run(){
        String username = account.getText().toString();
        String pw = password.getText().toString();
        Message msg = new Message();
        try {
            httpInfo.getInfoFromWeb(username, pw, DEVICE_ID);
        }catch (Exception e) {
            Log.e("eeeeeeeee",e.toString());
        }
        if(httpInfo.status=="0"){
            httpInfo.updataLineNum();
            msg.what = 0;
            mHandler.sendMessage(msg);
            Intent i = new Intent(myApplication.getContext(),Activity_setLineNum.class);
            myApplication.getContext().startActivity(i);
            Activity_logIn.this.dismiss();
        }
        else {
            msg.what = 1;
            mHandler.sendMessage(msg);
        }
    }
}
private Handler mHandler = new Handler(){
    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        switch (msg.what) {
            case 0:
                Toast.makeText(getContext(), "登陆成功", Toast.LENGTH_SHORT).show();
                break;
            case 1:
                Toast.makeText(getContext(), httpInfo.message, Toast.LENGTH_SHORT).show();
                break;
        }
    }
};

}