android 對象傳輸及parcel機制

標籤：

  在開發中不少要用到Activity直接傳輸對象，下面我們來看看，其實跟java裡面差不多
   自訂對象的傳遞：通過intent傳遞自訂對象的方法有兩個
  第一是實現Serialization介面；
  第二是實現Parcelable介面；

  下面來看個例子：

  

package com.example.bean; import java.io.Serializable; public class Bed implements Serializable {  private String name;  private int number;  public String getName() {   return name;  }  public void setName(String name) {   this.name = name;  }  public int getNumber() {   return number;  }  public void setNumber(int number) {   this.number = number;  }  @Override  public String toString() {   return "Name：" + getName() + "，Number：" + getNumber();  } }

package com.example.bean; import android.os.Parcel; import android.os.Parcelable; public class Patient implements Parcelable { private String name; private int number; public String getName() {  return name; } public void setName(String name) {  this.name = name; } public int getNumber() {  return number; } public void setNumber(int number) {  this.number = number; } public static final Parcelable.Creator<Patient> CREATOR = new Parcelable.Creator<Patient>() {  public Patient createFromParcel(Parcel p) {   Patient patient = new Patient();   patient.name = p.readString();   patient.number = p.readInt();   return patient;  }  public Patient[] newArray(int size) {   return new Patient[size];  } }; @Override public int describeContents() {  return 0; } /** * *@desc  註：這裡的write方法和createFromParcel裡的一一對應，不然createFromParcel都是p.readString()，你怎麼知道是哪一個 * */ @Override public void writeToParcel(Parcel p, int flags) {  p.writeString(name);  p.writeInt(number); } @Override public String toString() {  return "Name：" + getName() + "，Number：" + getNumber(); }}

TestActivity.java：    StringBuilder sb = new StringBuilder();  sb.append("Serializable Bed對象\n");  Bed bed = (Bed) getIntent().getExtras().get("bed");  sb.append(bed.toString());  sb.append("\n\nList<Serializable Bed>集合\n");  List<Bed> listBed = (List<Bed>) getIntent()    .getSerializableExtra("beds");  for (int i = 0; i < listBed.size(); i++) {   sb.append(listBed.get(i).toString() + "；");  }  sb.append("\n\nParcelable Patient對象\n");  Patient patient = getIntent().getParcelableExtra("patient1");  sb.append(patient.toString());  sb.append("\n\nParcelable Patient byte[]\n");  byte[] data = getIntent().getByteArrayExtra("patient2");  if (data != null) {   Parcel in = Parcel.obtain();   in.unmarshall(data, 0, data.length);   in.setDataPosition(0);   patient = Patient.CREATOR.createFromParcel(in);  }  sb.append(patient.toString());  sb.append("\n\nString數組\n");  String[] str = getIntent().getStringArrayExtra("patients");  for (int i = 0; i < str.length; i++) {   sb.append(str[i]);  }  TextView tv = (TextView) findViewById(R.id.tv);  tv.setText(sb);

 

android 對象傳輸及parcel機制