我想问你，当TextView中的文本等于指定单词或为空时，如何以编程方式更改CardView中LinearLayout的背景颜色。例如，field1获得字符串“ red”，则LinearLayout的背景变为红色。我正在从JSON php文件中获取数据。
Mainactivity.class
public class Mainactivity extends AppCompatactivity {
private String jsonURL = "http://example.com/test.php";
private final int jsoncode = 1;
private RecyclerView recyclerView;
ArrayList<Model> ModelArrayList;
private Adapter adapter;
private static ProgressDialog mProgressDialog;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recycler);
fetchJSON();
}
@SuppressLint("StaticFieldLeak")
private void fetchJSON(){
new AsyncTask<Void,Void,String>(){
protected String doInBackground(Void[] params) {
String response="";
HashMap<String,String> map=new HashMap<>();
try {
HttpRequest req = new HttpRequest(jsonURL);
response = req.prepare(HttpRequest.Method.POST).withData(map).sendAndReadString();
} catch (Exception e) {
response=e.getMessage();
}
return response;
}
protected void onPostExecute(String result) {
//do something with response
onTaskCompleted(result,jsoncode);
}
}.execute();
}
public void onTaskCompleted(String response,int serviceCode) {
Log.d("responsejson",response.toString());
switch (serviceCode) {
case jsoncode:
if (isSuccess(response)) {
removeSimpleProgressDialog(); //will remove progress dialog
ModelArrayList = getInfo(response);
adapter = new Adapter(this,ModelArrayList);
recyclerView.setadapter(adapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getapplicationContext(),LinearLayoutManager.VERTICAL,false));
}else {
Toast.makeText(Mainactivity.this,getErrorCode(response),Toast.LENGTH_SHORT).show();
}
}
}
public ArrayList<Model> getInfo(String response) {
ArrayList<Model> ModelArrayList = new ArrayList<>();
try {
JSONObject jsonObject = new JSONObject(response);
if (jsonObject.getString("status").equals("true")) {
JSONArray dataArray = jsonObject.getJSONArray("data");
for (int i = 0; i < dataArray.length(); i++) {
Model fieldsModel = new Model();
JSONObject dataobj = dataArray.getJSONObject(i);
fieldsModel.setfield1(dataobj.getString("field1"));
fieldsModel.setfield2(dataobj.getString("field2"));
ModelArrayList.add(fieldsModel);
}
}
} catch (JSONException e) {
e.printStackTrace();
}
return ModelArrayList;
}
public boolean isSuccess(String response) {
try {
JSONObject jsonObject = new JSONObject(response);
if (jsonObject.optString("status").equals("true")) {
return true;
} else {
return false;
}
} catch (JSONException e) {
e.printStackTrace();
}
return false;
}
public String getErrorCode(String response) {
try {
JSONObject jsonObject = new JSONObject(response);
return jsonObject.getString("message");
} catch (JSONException e) {
e.printStackTrace();
}
return "No data";
}
}
Adapter.class
public class Adapter extends RecyclerView.Adapter<Adapter.MyViewHolder> {
private LayoutInflater inflater;
private ArrayList<Model> ModelArrayList;
public Adapter(Context ctx,ArrayList<Model> rogerModelArrayList){
inflater = LayoutInflater.from(ctx);
this.ModelArrayList = rogerModelArrayList;
}
@Override
public Adapter.MyViewHolder onCreateViewHolder(ViewGroup parent,int viewType) {
View view = inflater.inflate(R.layout.rv_item,parent,false);
MyViewHolder holder = new MyViewHolder(view);
return holder;
}
@Override
public void onBindViewHolder(Adapter.MyViewHolder holder,int position) {
holder.field1.setText(ModelArrayList.get(position).getField1());
holder.field2.setText(ModelArrayList.get(position).getField2());
}
@Override
public int getItemCount() {
return ModelArrayList.size();
}
class MyViewHolder extends RecyclerView.ViewHolder{
TextView field1,field2;
public MyViewHolder(View itemView) {
super(itemView);
field1 = (TextView) itemView.findViewById(R.id.field1);
field2 = (TextView) itemView.findViewById(R.id.field2);
}
}
}
Model.class
public class Model {
private String field1,field2;
public String getField1() {
return field1;
}
public void setfield1(String field1) {
this.field1 = field1;
}
public String getField2() {
return field2;
}
public void setfield2(String field2) {
this.field2 = field2;
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<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"
android:orientation="vertical"
android:background="#cd15e6"
tools:context=".Mainactivity">
** <android.support.v7.widget.RecyclerView
android:id="@+id/recycler"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dp"
android:layout_marginTop="15dp"/> **
</LinearLayout>
rv_item.xml 这是我要更改颜色 LL_background
的LinearLayout<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.CardView
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp"
app:cardCornerRadius="5dp">
<LinearLayout
android:id="@+id/LL_background"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="100dp"
android:layout_marginLeft="10dp"
android:layout_marginTop="10dp"
android:orientation="vertical">
<TextView
android:id="@+id/field1"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_marginTop="5dp"
android:layout_weight="1"
android:text="ddd"
android:textColor="#000"
android:textStyle="bold" />
<TextView
android:id="@+id/field2"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1"
android:text="ddd"
android:textColor="#000"
android:textStyle="bold" />
</LinearLayout>
</LinearLayout>
</android.support.v7.widget.CardView>
</LinearLayout>
请检查我的项目并分享您的想法。非常感谢?