android中Spinner所遇到的問題

好久沒更新博客了，最近比較忙，在學android的基礎知識，疑惑也不是很多，知道今晚在重寫BaseAdapter的時候遇到了一個平常都不會注意的小問題

請看下面代碼：

定義User_Type類

package com.example.zhao.standardview;

import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;

/**
 * Created by zhao on 2017/5/5.
 */

public class User_type
{
   private String muserName;
    private String muserAddress;
    public User_type(String Name,String Address)
    {
        muserAddress = Address;
        muserName = Name;
    }
    public String getUserName()
    {
        return muserName;
    }

    public void setUserName(String userName)
    {
        this.muserName = userName;
    }

    public String getUserAddress()
    {
        return muserAddress;
    }

    public void setUserAddress(String userAddress)
    {
        this.muserAddress = userAddress;
    }



}

重寫BaseAdapter

package com.example.zhao.standardview;

import android.content.Context;
import android.text.Layout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by zhao on 2017/5/5.
 */

public class User_Adapter extends BaseAdapter
{
    List<User_type> user_types ;
    Context context;
    public User_Adapter (Context mcontext, List<User_type> muser_type)
    {
        this.user_types = muser_type;
        this.context = mcontext;
    }
    @Override
    public int getCount()
    {
        return user_types.size();
    }

    @Override
    public Object getItem(int position)
    {
        return user_types.get(position);
    }

    @Override
    public long getItemId(int position)
    {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        convertView = LayoutInflater.from(context).inflate(R.layout.user_layout,null);
        TextView textView1 = (TextView) convertView.findViewById(R.id.textView1);
        TextView textView2 = (TextView) convertView.findViewById(R.id.textView2);
        textView1.setText(user_types.get(position).getUserName());
        textView2.setText(user_types.get(position).getUserAddress());
        return convertView;
    }
}

UI界面

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <TextView
        android:text="TextView"
        android:textSize="26dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView1"
        android:layout_weight="1"
        android:drawableLeft="@android:drawable/btn_star"
        />

    <TextView
        android:text="TextView"
        android:textSize="26dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView2"
        android:layout_weight="1"/>
</LinearLayout>

主類

package com.example.zhao.standardview;

import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.support.annotation.RequiresApi;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Html;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.style.ClickableSpan;
import android.text.style.ImageSpan;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;

import static android.text.Html.FROM_HTML_MODE_LEGACY;

public class MainActivity extends AppCompatActivity
{

    @RequiresApi(api = Build.VERSION_CODES.N)
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
     /*   showTextView();
        showspinner();*/
        showspinner2( );
    }
    private  void showspinner2( )
    {
        Spinner spinner = (Spinner) findViewById(R.id.spinner);
        ArrayList<User_type> users = new ArrayList<User_type>();

        users.add(new User_type("張三","山東"));
        users.add(new User_type("李四","山西"));
        users.add(new User_type("王五","陝西"));
        users.add(new User_type("劉海","江蘇"));
        User_Adapter adapter = new User_Adapter(this,users);
        spinner.setAdapter(adapter);

    }
}

剛寫完的時候，一直出錯，改了半個多小時也不對，最後想到問題出現在UI界面的代碼上，我在第一個TextView上畫了一個圖片竟然是gif格式的，導致安裝apk後，應用程序老是報錯，所以以後要注意，圖片最好用png格式，gif格式千萬別用