Android學習之-------recycle實現瀑布流

recyc瀑布流

一.效果：

代碼實現：

package com.example.app3;

import android.graphics.Canvas;
import android.graphics.drawable.ColorDrawable;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.DividerItemDecoration;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.view.View;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;

public class MainActivity extends AppCompatActivity {

    RecyclerView recyclerView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        recyclerView = findViewById(R.id.recycler);
        getSupportActionBar().hide();

//        LinearLayoutManager manager = new LinearLayoutManager(this);
//        manager.setOrientation(LinearLayoutManager.VERTICAL); //列表

        GridLayoutManager gridLayoutManager = new GridLayoutManager(this,3); //網格


        StaggeredGridLayoutManager manager = new StaggeredGridLayoutManager(2,StaggeredGridLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(manager);

        ArrayList<Integer> strings = new ArrayList<>();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
        String currentData = dateFormat.format(new Date());

        strings.add(R.mipmap.aa);
        strings.add(R.mipmap.bb);
        strings.add(R.mipmap.cc);
        strings.add(R.mipmap.dd);
        strings.add(R.mipmap.ee);
        strings.add(R.mipmap.ff);
        strings.add(R.mipmap.gg);
        strings.add(R.mipmap.hh);
        strings.add(R.mipmap.jj);
        strings.add(R.mipmap.kk);
        strings.add(R.mipmap.ff);


        MyAdapter myAdapter = new MyAdapter(strings,this);
        recyclerView.setAdapter(myAdapter);


        DefaultItemAnimator defaultItemAnimator  = new DefaultItemAnimator();
        defaultItemAnimator.setAddDuration(2000);
        defaultItemAnimator.setRemoveDuration(2000);
        recyclerView.setItemAnimator(defaultItemAnimator);  //設置刪除和添加的動畫

        DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(this,DividerItemDecoration.VERTICAL);
//        dividerItemDecoration.setDrawable(new ColorDrawable(234234));
        recyclerView.addItemDecoration(dividerItemDecoration);  //分割線

    }
}

適配器

package com.example.app3;

import android.content.Context;
import android.support.annotation.NonNull;
import android.support.v7.view.menu.MenuView;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHoder> {


    ArrayList<Integer> strings;
    Context context;


    public MyAdapter(ArrayList<Integer> strings,Context context)
    {
        this.strings = strings;
        this.context = context;
    }

    @NonNull
    @Override
    public MyViewHoder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
        //返回viewHolder
        View itemView = LayoutInflater.from(context).inflate(R.layout.item_layout,null); //視圖
        MyViewHoder viewHoder = new MyViewHoder(itemView);
        return viewHoder;
    }

    @Override
    public void onBindViewHolder(@NonNull MyViewHoder myViewHoder, final int i) {

        int hightValue =(int)Math.random()*401+100;

        LinearLayout.LayoutParams layoutParams = (LinearLayout.LayoutParams) myViewHoder.imageView.getLayoutParams();

        layoutParams.height = hightValue;
        myViewHoder.imageView.setLayoutParams(layoutParams);

        myViewHoder.imageView.setImageResource(strings.get(i));

        myViewHoder.imageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                strings.remove(i);
                notifyItemRemoved(i); //更新
                notifyItemRangeChanged(i,strings.size());
            }
        });

        myViewHoder.imageView.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {

                strings.add(R.mipmap.kk);
                notifyItemInserted(i);
                return true;
            }
        });
    }

    @Override
    public int getItemCount() {
        return strings.size();
    }


    class MyViewHoder extends RecyclerView.ViewHolder
    {
        ImageView imageView;
        public MyViewHoder(@NonNull View itemView) {
            super(itemView);

            imageView = itemView.findViewById(R.id.text);
        }
    }

}

佈局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler"
        android:layout_width="match_parent"
        android:layout_height="match_parent">


    </android.support.v7.widget.RecyclerView>

</LinearLayout>

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <ImageView
        android:id="@+id/text"
        android:layout_width="match_parent"
        android:scaleType="fitXY"
        android:layout_height="wrap_content" />

</LinearLayout>