我的一個程式中有一個listivew串列頁，我想點擊串列頁其中一項跳轉頁面，跳轉后的頁面中顯示相應的資料庫中的圖片和資料，求大佬幫助
下面是串列頁的activity，有一些地方看不懂，希望大佬也可以幫我解釋一下
/**
* 歷史資料activity
*/
public class HistoryActivity extends AppCompatActivity {
@BindView(R.id.lv_history)
ListView lvHistory;
List<History.HistoryBean> historyBeanList = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_history);
ButterKnife.bind(this);
getData();
}
/**
* 獲取歷史資料
*/
private void getData() {
SharedPreferences sharedPreferences = getSharedPreferences("login", MODE_PRIVATE);
String url = "http://" + HttpConn.IP + "/App/history/getcid";
OkHttpUtils
.get()
.url(url)
.addParams("cid", sharedPreferences.getString("cid", null))
.build()
.execute(new StringCallback() {
@Override
public void onError(Call call, Exception e, int id) {
Toast.makeText(HistoryActivity.this, "網路錯誤", Toast.LENGTH_SHORT).show();
Log.e("LoginActivity", "onError: " + e);
}
@Override
public void onResponse(String response, int id) {
Gson gson = new Gson();
History history = gson.fromJson(response,History.class);
historyBeanList = history.getHistory();
/**
* listview設定adapter
*/
HistoryListAdapter adapter = new HistoryListAdapter(HistoryActivity.this,historyBeanList);
lvHistory.setAdapter(adapter);
}
});
}
}
uj5u.com熱心網友回復：
你先說一下你哪里看不懂？ 這個Activity寫得很清楚了啊。。就是一個網路請求資料，Gson決議，設定lvHistory的Adapter資料就沒了。。
你去看看這個類 History.class 里的資料項與你的請求資料是否是相同的欄位，要保持一致的
這個lvHistory的單擊事件呢？ 跳轉的時候攜帶資料跳轉就好了
uj5u.com熱心網友回復：
lvHistory.setOnItemClickListener(new AdapterView.OnItemClickListener() {@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent=new Intent(this,要跳轉的頁面.class)
intent.putExtra("mystring",historyBeanList.get(position).get你要的)
startactivity(intent);
}
});
在接受的頁面 Intent intent=getIntent();
str= intent.getstringExtra("mystring")
uj5u.com熱心網友回復：
串列adapter 元素加事件，打開新的activityuj5u.com熱心網友回復：
怎么能實作攜帶資料跳轉呢uj5u.com熱心網友回復：
我這么做了他告訴我構造器有問題錯誤: 對于Intent(<匿名OnItemClickListener>,Class<DetailActivity>), 找不到合適的構造器
構造器 Intent.Intent(String,Uri)不適用
(引數不匹配; <匿名OnItemClickListener>無法轉換為String)
構造器 Intent.Intent(Context,Class<?>)不適用
(引數不匹配; <匿名OnItemClickListener>無法轉換為Context)
uj5u.com熱心網友回復：
你給HistoryListAdapter 類里傳了HistoryActivity.thisHistoryListAdapter adapter = new HistoryListAdapter(HistoryActivity.this,historyBeanList);
然后 public HistoryListAdapter (Context context, List<History.HistoryBean> dataList) {
this.context = context//這里有個 context
}
intent構造器里 就放這個 context
Intent intent=new Intent(context,要跳轉的頁面.class)
uj5u.com熱心網友回復：
報錯資訊：
附上相關的代碼：
HistoryActivity：
/**
* 歷史資料activity
*/
public class HistoryActivity extends AppCompatActivity {
private Context context;
@BindView(R.id.lv_history)
ListView lvHistory;
List<History.HistoryBean> historyBeanList = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_history);
ButterKnife.bind(this);
getData();
}
/**
* 獲取歷史資料
*/
private void getData() {
SharedPreferences sharedPreferences = getSharedPreferences("login", MODE_PRIVATE);
String url = "http://" + HttpConn.IP + "/App/history/getcid";
OkHttpUtils
.get()
.url(url)
.addParams("cid", sharedPreferences.getString("cid", null))
.build()
.execute(new StringCallback() {
@Override
public void onError(Call call, Exception e, int id) {
Toast.makeText(HistoryActivity.this, "網路錯誤", Toast.LENGTH_SHORT).show();
Log.e("LoginActivity", "onError: " + e);
}
@Override
public void onResponse(String response, int id) {
Gson gson = new Gson();
History history = gson.fromJson(response,History.class);
historyBeanList = history.getHistory();
/**
* listview設定adapter
*/
HistoryListAdapter adapter = new HistoryListAdapter(HistoryActivity.this,historyBeanList);
lvHistory.setAdapter(adapter);
lvHistory.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent=new Intent(context,DetailActivity.class);
intent.putExtra("mystring",historyBeanList.get(position).getPhoto());
startActivity(intent);
}
});
}
});
}
}
HistoryListAdapter：
public class HistoryListAdapter extends BaseAdapter {
private Context context;
public HistoryListAdapter(Context context, List<History.HistoryBean> historyBeanList) {
this.context = context;
this.historyBeanList = historyBeanList;
}
private List<History.HistoryBean> historyBeanList;
@Override
public int getCount() {
return historyBeanList.size();
}
@Override
public Object getItem(int i) {
return null;
}
@Override
public long getItemId(int i) {
return 0;
}
@Override
public View getView(int i, View convertView, ViewGroup viewGroup) {
ViewHolder viewHolder = null;
View view = null;
if (convertView == null) {
viewHolder = new ViewHolder();
view = LayoutInflater.from(context).inflate(R.layout.item_history, null);
viewHolder.ivPhoto = view.findViewById(R.id.iv_photo);
viewHolder.tvTime = view.findViewById(R.id.tv_time);
view.setTag(viewHolder);
} else {
view = convertView;
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.ivPhoto.setImageBitmap(stringToBitmap(historyBeanList.get(i).getPhoto()));
viewHolder.tvTime.setText(" "+historyBeanList.get(i).getDate() + historyBeanList.get(i).getTime());
return view;
}
//將64編碼轉為Bitmap
public static Bitmap stringToBitmap(String photo_base64) {
Bitmap bitmap = null;
byte[] bitmapArry = Base64.decode(photo_base64, Base64.DEFAULT);
bitmap = BitmapFactory.decodeByteArray(bitmapArry, 0, bitmapArry.length);
return bitmap;
}
class ViewHolder {
ImageView ivPhoto;
TextView tvTime;
}
}
History：
public class History implements Serializable {
private List<HistoryBean> history;
public List<HistoryBean> getHistory() {
return history;
}
public void setHistory(List<HistoryBean> history) {
this.history = history;
}
public static class HistoryBean implements Serializable{
/**
* cid : 1
* date : 321
* info : 11
* oid : 1
* photo : 222
* time : 123
*/
private int cid;
private String date;
private String info;
private int oid;
private String photo;
private String time;
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
public String getInfo() {
return info;
}
public void setInfo(String info) {
this.info = info;
}
public int getOid() {
return oid;
}
public void setOid(int oid) {
this.oid = oid;
}
public String getPhoto() {
return photo;
}
public void setPhoto(String photo) {
this.photo = photo;
}
public String getTime() {
return time;
}
public void setTime(String time) {
this.time = time;
}
}
}
跳轉后的頁面DetailActivity：
public class DetailActivity extends AppCompatActivity {
public String str[];
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detail);
Intent intent=getIntent();
str=intent.getStringArrayExtra("mystring");
}
}
uj5u.com熱心網友回復：
emmmm HistoryActivity 這個類 里面 不要寫 private Context context ,把 Intent intent=new Intent(context,DetailActivity.class); 給我 改回來 改成Intent intent=new Intent(HistoryActivity .this,DetailActivity.class);
然后 至少 這個錯誤 就不會發生了
uj5u.com熱心網友回復：
是的，現在沒有錯誤了，但是跳入頁面后，頁面中沒有任何文字或圖片資料uj5u.com熱心網友回復：
DetailActivity 這個類 拿到傳過來的值嗎？拿到的話你就弄個 textView 來顯示。
uj5u.com熱心網友回復：
我拿到的應該是一張圖片，但是被我拿來放在這個字串中怎么以圖片形式顯示呢
這段是我在HistoryActivity拿值的代碼：
lvHistory.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent=new Intent(HistoryActivity.this,DetailActivity.class);
intent.putExtra("myphoto",historyBeanList.get(position).getPhoto());
startActivity(intent);
}
這段是在DetailActivity 中想把值顯示出來的代碼
public class DetailActivity extends AppCompatActivity {
public String str[];
@BindView(R.id.iv_photo2)
ImageView ivPhoto2;
// public String iv_photo2[];
//public ImageView iv_photo2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detail);
Intent intent=getIntent();
str=intent.getStringArrayExtra("myphoto");
// iv_photo2=intent.getStringArrayExtra("mystring");
// ivPhoto2.setImageBitmap(intent.getStringArrayExtra());
}
uj5u.com熱心網友回復：
嗯 友情提示 bitmap 或者 picasso 可以幫到你uj5u.com熱心網友回復：
context 沒有賦值onCreate()下加上
context =this;
uj5u.com熱心網友回復：
可以用這個追蹤下方法順序 看看 https://blog.csdn.net/qq_27512671/article/details/104949747轉載請註明出處，本文鏈接：https://www.uj5u.com/yidong/53229.html
標籤：Android