仿微信主界面

看了鸿洋大神的慕课视频，觉得讲的实在是好，自己手打了一遍，我还是记录一下。

package com.example.weixintest;
import java.util.ArrayList;
import java.util.List;
import com.jauker.widget.BadgeView;
import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Display;
import android.view.Window;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

public class MainActivity extends FragmentActivity {

    private ViewPager mViewPager;
    private FragmentPagerAdapter mAdapter;
    private List mDatas;
    private TextView mChatTextView;
    private TextView mFriendTextView;
    private TextView mContactTextView;
    private LinearLayout mChatLinearLayout;
    private BadgeView mBadgeView;//需要到gihub上下载BadgeView的包

    private ImageView mTabline;
    private int mScreen1_3; //屏幕宽度的1/3的距离

    private int mCurrentPageIndex;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //设置窗体风格，去actionBar
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);
        //这里是初始化Tabline的长度
        initTabline();
        initView();
    }

//获取屏幕宽度的1/3作为点9图片的长度
    private void initTabline() {
        mTabline = (ImageView) findViewById(R.id.id_iv_tabline);
        Display display = getWindow().getWindowManager().getDefaultDisplay();
        DisplayMetrics outMetrics = new DisplayMetrics();
        display.getMetrics(outMetrics);
        mScreen1_3 = outMetrics.widthPixels / 3;
        android.view.ViewGroup.LayoutParams lp = mTabline.getLayoutParams();
        lp.width = mScreen1_3;
        mTabline.setLayoutParams(lp);
    }

    // 初始化view
    @SuppressWarnings("deprecation")
    private void initView() {
        mViewPager = (ViewPager) findViewById(R.id.id_viewpager);
        mChatTextView = (TextView) findViewById(R.id.id_tv_chat);
        mFriendTextView = (TextView) findViewById(R.id.id_tv_friend);
        mContactTextView = (TextView) findViewById(R.id.id_tv_contact);
        mChatLinearLayout = (LinearLayout) findViewById(R.id.id_ll_chat);

        mDatas = new ArrayList();
        ChatMainTabFragment tab01 = new ChatMainTabFragment();
        FriendMainTabFragment tab02 = new FriendMainTabFragment();
        ContactMainTabFragment tab03 = new ContactMainTabFragment();

        mDatas.add(tab01);
        mDatas.add(tab02);
        mDatas.add(tab03);

        mAdapter = new FragmentPagerAdapter(getSupportFragmentManager()) {

            @Override
            public int getCount() {
                return mDatas.size();
            }

            @Override
            public Fragment getItem(int arg0) {
                return mDatas.get(arg0);
            }
        };
        mViewPager.setAdapter(mAdapter);


        mViewPager.setOnPageChangeListener(new OnPageChangeListener() {

            @Override
            public void onPageSelected(int position) {
                resetTextView();
                switch (position) {
                case 0:
                //mBadgeView != null这个意思是如果存在这个控件，就先remove掉
                    if (mBadgeView != null) {
                        mChatLinearLayout.removeView(mBadgeView);
                    }
                    //初始化BadgeView，取到父容器LinearLayout直接add进来
                    mBadgeView = new BadgeView(MainActivity.this);
                    mBadgeView.setBadgeCount(7);
                    mChatLinearLayout.addView(mBadgeView);

                    mChatTextView.setTextColor(Color.parseColor("#008000"));
                    break;
                case 1:
                    mFriendTextView.setTextColor(Color.parseColor("#008000"));
                    break;
                case 2:
                    mContactTextView.setTextColor(Color.parseColor("#008000"));
                    break;

                }
//选中页就是当前页的下标
                mCurrentPageIndex = position;
            }

            @Override
            public void onPageScrolled(int position, float positionOffset,
                    int positionOffsetPx) {
                    //这里打印的log可以得出以下的规律，不断地改变tabline距离左边的margin就可以了。
                Log.e("TAG", position + " , " + positionOffset + " , "
                        + positionOffsetPx);

                LinearLayout.LayoutParams lp = (android.widget.LinearLayout.LayoutParams) mTabline
                        .getLayoutParams();

                if (mCurrentPageIndex == 0 && position == 0)// 0->1
                {
                    lp.leftMargin = (int) (positionOffset * mScreen1_3 + mCurrentPageIndex
                            * mScreen1_3);
                } else if (mCurrentPageIndex == 1 && position == 0)// 1->0
                {
                    lp.leftMargin = (int) (mCurrentPageIndex * mScreen1_3 + (positionOffset - 1)
                            * mScreen1_3);
                } else if (mCurrentPageIndex == 1 && position == 1) // 1->2
                {
                    lp.leftMargin = (int) (mCurrentPageIndex * mScreen1_3 + positionOffset
                            * mScreen1_3);
                } else if (mCurrentPageIndex == 2 && position == 1) // 2->1
                {
                    lp.leftMargin = (int) (mCurrentPageIndex * mScreen1_3 + (positionOffset - 1)
                            * mScreen1_3);
                }
                //不要忘了最终设定mTabline距离左边的距离
                mTabline.setLayoutParams(lp);
            }

            @Override
            public void onPageScrollStateChanged(int arg0) {

            }
        });

    }

//不管选中那一页，只要是页面重新滚动了，就先初始化，再根据当前页码改变颜色
    protected void resetTextView() {
        mChatTextView.setTextColor(Color.BLACK);
        mFriendTextView.setTextColor(Color.BLACK);
        mContactTextView.setTextColor(Color.BLACK);
    }
}



//其中一个的fragment的代码
package com.example.weixintest;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class ChatMainTabFragment extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater,
            @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(R.layout.tab01, container, false);
    }

}